Merging upstream version 1.11.0+dfsg.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1412 insertions, 0 deletions

diff --git a/daemon/unit_test.c b/daemon/unit_test.c
new file mode 100644
index 000000000..9978647b4
--- /dev/null
+++ b/daemon/unit_test.c
@@ -0,0 +1,1412 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "common.h"
+
+static int check_number_printing(void) {
+    struct {
+        calculated_number n;
+        const char *correct;
+    } values[] = {
+            { .n = 0, .correct = "0" },
+            { .n = 0.0000001,   .correct = "0.0000001" },
+            { .n = 0.00000009,  .correct = "0.0000001" },
+            { .n = 0.000000001, .correct = "0" },
+            { .n = 99.99999999999999999, .correct = "100" },
+            { .n = -99.99999999999999999, .correct = "-100" },
+            { .n = 123.4567890123456789, .correct = "123.456789" },
+            { .n = 9999.9999999, .correct = "9999.9999999" },
+            { .n = -9999.9999999, .correct = "-9999.9999999" },
+            { .n = 0, .correct = NULL },
+    };
+
+    char netdata[50], system[50];
+    int i, failed = 0;
+    for(i = 0; values[i].correct ; i++) {
+        print_calculated_number(netdata, values[i].n);
+        snprintfz(system, 49, "%0.12" LONG_DOUBLE_MODIFIER, (LONG_DOUBLE)values[i].n);
+
+        int ok = 1;
+        if(strcmp(netdata, values[i].correct) != 0) {
+            ok = 0;
+            failed++;
+        }
+
+        fprintf(stderr, "'%s' (system) printed as '%s' (netdata): %s\n", system, netdata, ok?"OK":"FAILED");
+    }
+
+    if(failed) return 1;
+    return 0;
+}
+
+static int check_rrdcalc_comparisons(void) {
+    RRDCALC_STATUS a, b;
+
+    // make sure calloc() sets the status to UNINITIALIZED
+    memset(&a, 0, sizeof(RRDCALC_STATUS));
+    if(a != RRDCALC_STATUS_UNINITIALIZED) {
+        fprintf(stderr, "%s is not zero.\n", rrdcalc_status2string(RRDCALC_STATUS_UNINITIALIZED));
+        return 1;
+    }
+
+    a = RRDCALC_STATUS_REMOVED;
+    b = RRDCALC_STATUS_UNDEFINED;
+    if(!(a < b)) {
+        fprintf(stderr, "%s is not less than %s\n", rrdcalc_status2string(a), rrdcalc_status2string(b));
+        return 1;
+    }
+
+    a = RRDCALC_STATUS_UNDEFINED;
+    b = RRDCALC_STATUS_UNINITIALIZED;
+    if(!(a < b)) {
+        fprintf(stderr, "%s is not less than %s\n", rrdcalc_status2string(a), rrdcalc_status2string(b));
+        return 1;
+    }
+
+    a = RRDCALC_STATUS_UNINITIALIZED;
+    b = RRDCALC_STATUS_CLEAR;
+    if(!(a < b)) {
+        fprintf(stderr, "%s is not less than %s\n", rrdcalc_status2string(a), rrdcalc_status2string(b));
+        return 1;
+    }
+
+    a = RRDCALC_STATUS_CLEAR;
+    b = RRDCALC_STATUS_RAISED;
+    if(!(a < b)) {
+        fprintf(stderr, "%s is not less than %s\n", rrdcalc_status2string(a), rrdcalc_status2string(b));
+        return 1;
+    }
+
+    a = RRDCALC_STATUS_RAISED;
+    b = RRDCALC_STATUS_WARNING;
+    if(!(a < b)) {
+        fprintf(stderr, "%s is not less than %s\n", rrdcalc_status2string(a), rrdcalc_status2string(b));
+        return 1;
+    }
+
+    a = RRDCALC_STATUS_WARNING;
+    b = RRDCALC_STATUS_CRITICAL;
+    if(!(a < b)) {
+        fprintf(stderr, "%s is not less than %s\n", rrdcalc_status2string(a), rrdcalc_status2string(b));
+        return 1;
+    }
+
+    fprintf(stderr, "RRDCALC_STATUSes are sortable.\n");
+
+    return 0;
+}
+
+int check_storage_number(calculated_number n, int debug) {
+    char buffer[100];
+    uint32_t flags = SN_EXISTS;
+
+    storage_number s = pack_storage_number(n, flags);
+    calculated_number d = unpack_storage_number(s);
+
+    if(!does_storage_number_exist(s)) {
+        fprintf(stderr, "Exists flags missing for number " CALCULATED_NUMBER_FORMAT "!\n", n);
+        return 5;
+    }
+
+    calculated_number ddiff = d - n;
+    calculated_number dcdiff = ddiff * 100.0 / n;
+
+    if(dcdiff < 0) dcdiff = -dcdiff;
+
+    size_t len = (size_t)print_calculated_number(buffer, d);
+    calculated_number p = str2ld(buffer, NULL);
+    calculated_number pdiff = n - p;
+    calculated_number pcdiff = pdiff * 100.0 / n;
+    if(pcdiff < 0) pcdiff = -pcdiff;
+
+    if(debug) {
+        fprintf(stderr,
+            CALCULATED_NUMBER_FORMAT " original\n"
+            CALCULATED_NUMBER_FORMAT " packed and unpacked, (stored as 0x%08X, diff " CALCULATED_NUMBER_FORMAT ", " CALCULATED_NUMBER_FORMAT "%%)\n"
+            "%s printed after unpacked (%zu bytes)\n"
+            CALCULATED_NUMBER_FORMAT " re-parsed from printed (diff " CALCULATED_NUMBER_FORMAT ", " CALCULATED_NUMBER_FORMAT "%%)\n\n",
+            n,
+            d, s, ddiff, dcdiff,
+            buffer, len,
+            p, pdiff, pcdiff
+        );
+        if(len != strlen(buffer)) fprintf(stderr, "ERROR: printed number %s is reported to have length %zu but it has %zu\n", buffer, len, strlen(buffer));
+        if(dcdiff > ACCURACY_LOSS) fprintf(stderr, "WARNING: packing number " CALCULATED_NUMBER_FORMAT " has accuracy loss " CALCULATED_NUMBER_FORMAT " %%\n", n, dcdiff);
+        if(pcdiff > ACCURACY_LOSS) fprintf(stderr, "WARNING: re-parsing the packed, unpacked and printed number " CALCULATED_NUMBER_FORMAT " has accuracy loss " CALCULATED_NUMBER_FORMAT " %%\n", n, pcdiff);
+    }
+
+    if(len != strlen(buffer)) return 1;
+    if(dcdiff > ACCURACY_LOSS) return 3;
+    if(pcdiff > ACCURACY_LOSS) return 4;
+    return 0;
+}
+
+calculated_number storage_number_min(calculated_number n) {
+    calculated_number r = 1, last;
+
+    do {
+        last = n;
+        n /= 2.0;
+        storage_number t = pack_storage_number(n, SN_EXISTS);
+        r = unpack_storage_number(t);
+    } while(r != 0.0 && r != last);
+
+    return last;
+}
+
+void benchmark_storage_number(int loop, int multiplier) {
+    int i, j;
+    calculated_number n, d;
+    storage_number s;
+    unsigned long long user, system, total, mine, their;
+
+    char buffer[100];
+
+    struct rusage now, last;
+
+    fprintf(stderr, "\n\nBenchmarking %d numbers, please wait...\n\n", loop);
+
+    // ------------------------------------------------------------------------
+
+    fprintf(stderr, "SYSTEM  LONG DOUBLE    SIZE: %zu bytes\n", sizeof(calculated_number));
+    fprintf(stderr, "NETDATA FLOATING POINT SIZE: %zu bytes\n", sizeof(storage_number));
+
+    mine = (calculated_number)sizeof(storage_number) * (calculated_number)loop;
+    their = (calculated_number)sizeof(calculated_number) * (calculated_number)loop;
+
+    if(mine > their) {
+        fprintf(stderr, "\nNETDATA NEEDS %0.2" LONG_DOUBLE_MODIFIER " TIMES MORE MEMORY. Sorry!\n", (LONG_DOUBLE)(mine / their));
+    }
+    else {
+        fprintf(stderr, "\nNETDATA INTERNAL FLOATING POINT ARITHMETICS NEEDS %0.2" LONG_DOUBLE_MODIFIER " TIMES LESS MEMORY.\n", (LONG_DOUBLE)(their / mine));
+    }
+
+    fprintf(stderr, "\nNETDATA FLOATING POINT\n");
+    fprintf(stderr, "MIN POSITIVE VALUE " CALCULATED_NUMBER_FORMAT "\n", storage_number_min(1));
+    fprintf(stderr, "MAX POSITIVE VALUE " CALCULATED_NUMBER_FORMAT "\n", (calculated_number)STORAGE_NUMBER_POSITIVE_MAX);
+    fprintf(stderr, "MIN NEGATIVE VALUE " CALCULATED_NUMBER_FORMAT "\n", (calculated_number)STORAGE_NUMBER_NEGATIVE_MIN);
+    fprintf(stderr, "MAX NEGATIVE VALUE " CALCULATED_NUMBER_FORMAT "\n", -storage_number_min(1));
+    fprintf(stderr, "Maximum accuracy loss: " CALCULATED_NUMBER_FORMAT "%%\n\n\n", (calculated_number)ACCURACY_LOSS);
+
+    // ------------------------------------------------------------------------
+
+    fprintf(stderr, "INTERNAL LONG DOUBLE PRINTING: ");
+    getrusage(RUSAGE_SELF, &last);
+
+    // do the job
+    for(j = 1; j < 11 ;j++) {
+        n = STORAGE_NUMBER_POSITIVE_MIN * j;
+
+        for(i = 0; i < loop ;i++) {
+            n *= multiplier;
+            if(n > STORAGE_NUMBER_POSITIVE_MAX) n = STORAGE_NUMBER_POSITIVE_MIN;
+
+            print_calculated_number(buffer, n);
+        }
+    }
+
+    getrusage(RUSAGE_SELF, &now);
+    user   = now.ru_utime.tv_sec * 1000000ULL + now.ru_utime.tv_usec - last.ru_utime.tv_sec * 1000000ULL + last.ru_utime.tv_usec;
+    system = now.ru_stime.tv_sec * 1000000ULL + now.ru_stime.tv_usec - last.ru_stime.tv_sec * 1000000ULL + last.ru_stime.tv_usec;
+    total  = user + system;
+    mine = total;
+
+    fprintf(stderr, "user %0.5" LONG_DOUBLE_MODIFIER", system %0.5" LONG_DOUBLE_MODIFIER ", total %0.5" LONG_DOUBLE_MODIFIER "\n", (LONG_DOUBLE)(user / 1000000.0), (LONG_DOUBLE)(system / 1000000.0), (LONG_DOUBLE)(total / 1000000.0));
+
+    // ------------------------------------------------------------------------
+
+    fprintf(stderr, "SYSTEM   LONG DOUBLE PRINTING: ");
+    getrusage(RUSAGE_SELF, &last);
+
+    // do the job
+    for(j = 1; j < 11 ;j++) {
+        n = STORAGE_NUMBER_POSITIVE_MIN * j;
+
+        for(i = 0; i < loop ;i++) {
+            n *= multiplier;
+            if(n > STORAGE_NUMBER_POSITIVE_MAX) n = STORAGE_NUMBER_POSITIVE_MIN;
+            snprintfz(buffer, 100, CALCULATED_NUMBER_FORMAT, n);
+        }
+    }
+
+    getrusage(RUSAGE_SELF, &now);
+    user   = now.ru_utime.tv_sec * 1000000ULL + now.ru_utime.tv_usec - last.ru_utime.tv_sec * 1000000ULL + last.ru_utime.tv_usec;
+    system = now.ru_stime.tv_sec * 1000000ULL + now.ru_stime.tv_usec - last.ru_stime.tv_sec * 1000000ULL + last.ru_stime.tv_usec;
+    total  = user + system;
+    their = total;
+
+    fprintf(stderr, "user %0.5" LONG_DOUBLE_MODIFIER ", system %0.5" LONG_DOUBLE_MODIFIER ", total %0.5" LONG_DOUBLE_MODIFIER "\n", (LONG_DOUBLE)(user / 1000000.0), (LONG_DOUBLE)(system / 1000000.0), (LONG_DOUBLE)(total / 1000000.0));
+
+    if(mine > total) {
+        fprintf(stderr, "NETDATA CODE IS SLOWER %0.2" LONG_DOUBLE_MODIFIER " %%\n", (LONG_DOUBLE)(mine * 100.0 / their - 100.0));
+    }
+    else {
+        fprintf(stderr, "NETDATA CODE IS  F A S T E R  %0.2" LONG_DOUBLE_MODIFIER " %%\n", (LONG_DOUBLE)(their * 100.0 / mine - 100.0));
+    }
+
+    // ------------------------------------------------------------------------
+
+    fprintf(stderr, "\nINTERNAL LONG DOUBLE PRINTING WITH PACK / UNPACK: ");
+    getrusage(RUSAGE_SELF, &last);
+
+    // do the job
+    for(j = 1; j < 11 ;j++) {
+        n = STORAGE_NUMBER_POSITIVE_MIN * j;
+
+        for(i = 0; i < loop ;i++) {
+            n *= multiplier;
+            if(n > STORAGE_NUMBER_POSITIVE_MAX) n = STORAGE_NUMBER_POSITIVE_MIN;
+
+            s = pack_storage_number(n, 1);
+            d = unpack_storage_number(s);
+            print_calculated_number(buffer, d);
+        }
+    }
+
+    getrusage(RUSAGE_SELF, &now);
+    user   = now.ru_utime.tv_sec * 1000000ULL + now.ru_utime.tv_usec - last.ru_utime.tv_sec * 1000000ULL + last.ru_utime.tv_usec;
+    system = now.ru_stime.tv_sec * 1000000ULL + now.ru_stime.tv_usec - last.ru_stime.tv_sec * 1000000ULL + last.ru_stime.tv_usec;
+    total  = user + system;
+    mine = total;
+
+    fprintf(stderr, "user %0.5" LONG_DOUBLE_MODIFIER ", system %0.5" LONG_DOUBLE_MODIFIER ", total %0.5" LONG_DOUBLE_MODIFIER "\n", (LONG_DOUBLE)(user / 1000000.0), (LONG_DOUBLE)(system / 1000000.0), (LONG_DOUBLE)(total / 1000000.0));
+
+    if(mine > their) {
+        fprintf(stderr, "WITH PACKING UNPACKING NETDATA CODE IS SLOWER %0.2" LONG_DOUBLE_MODIFIER " %%\n", (LONG_DOUBLE)(mine * 100.0 / their - 100.0));
+    }
+    else {
+        fprintf(stderr, "EVEN WITH PACKING AND UNPACKING, NETDATA CODE IS  F A S T E R  %0.2" LONG_DOUBLE_MODIFIER " %%\n", (LONG_DOUBLE)(their * 100.0 / mine - 100.0));
+    }
+
+    // ------------------------------------------------------------------------
+
+}
+
+static int check_storage_number_exists() {
+    uint32_t flags = SN_EXISTS;
+
+
+    for(flags = 0; flags < 7 ; flags++) {
+        if(get_storage_number_flags(flags << 24) != flags << 24) {
+            fprintf(stderr, "Flag 0x%08x is not checked correctly. It became 0x%08x\n", flags << 24, get_storage_number_flags(flags << 24));
+            return 1;
+        }
+    }
+
+    flags = SN_EXISTS;
+    calculated_number n = 0.0;
+
+    storage_number s = pack_storage_number(n, flags);
+    calculated_number d = unpack_storage_number(s);
+    if(get_storage_number_flags(s) != flags) {
+        fprintf(stderr, "Wrong flags. Given %08x, Got %08x!\n", flags, get_storage_number_flags(s));
+        return 1;
+    }
+    if(n != d) {
+        fprintf(stderr, "Wrong number returned. Expected " CALCULATED_NUMBER_FORMAT ", returned " CALCULATED_NUMBER_FORMAT "!\n", n, d);
+        return 1;
+    }
+
+    return 0;
+}
+
+int unit_test_storage()
+{
+    if(check_storage_number_exists()) return 0;
+
+    calculated_number c, a = 0;
+    int i, j, g, r = 0;
+
+    for(g = -1; g <= 1 ; g++) {
+        a = 0;
+
+        if(!g) continue;
+
+        for(j = 0; j < 9 ;j++) {
+            a += 0.0000001;
+            c = a * g;
+            for(i = 0; i < 21 ;i++, c *= 10) {
+                if(c > 0 && c < STORAGE_NUMBER_POSITIVE_MIN) continue;
+                if(c < 0 && c > STORAGE_NUMBER_NEGATIVE_MAX) continue;
+
+                if(check_storage_number(c, 1)) return 1;
+            }
+        }
+    }
+
+    benchmark_storage_number(1000000, 2);
+    return r;
+}
+
+int unit_test_str2ld() {
+    char *values[] = {
+            "1.2345678", "-35.6", "0.00123", "23842384234234.2", ".1", "1.2e-10",
+            "hello", "1wrong", "nan", "inf", NULL
+    };
+
+    int i;
+    for(i = 0; values[i] ; i++) {
+        char *e_mine = "hello", *e_sys = "world";
+        LONG_DOUBLE mine = str2ld(values[i], &e_mine);
+        LONG_DOUBLE sys = strtold(values[i], &e_sys);
+
+        if(isnan(mine)) {
+            if(!isnan(sys)) {
+                fprintf(stderr, "Value '%s' is parsed as %" LONG_DOUBLE_MODIFIER ", but system believes it is %" LONG_DOUBLE_MODIFIER ".\n", values[i], mine, sys);
+                return -1;
+            }
+        }
+        else if(isinf(mine)) {
+            if(!isinf(sys)) {
+                fprintf(stderr, "Value '%s' is parsed as %" LONG_DOUBLE_MODIFIER ", but system believes it is %" LONG_DOUBLE_MODIFIER ".\n", values[i], mine, sys);
+                return -1;
+            }
+        }
+        else if(mine != sys && abs(mine-sys) > 0.000001) {
+            fprintf(stderr, "Value '%s' is parsed as %" LONG_DOUBLE_MODIFIER ", but system believes it is %" LONG_DOUBLE_MODIFIER ", delta %" LONG_DOUBLE_MODIFIER ".\n", values[i], mine, sys, sys-mine);
+            return -1;
+        }
+
+        if(e_mine != e_sys) {
+            fprintf(stderr, "Value '%s' is parsed correctly, but endptr is not right\n", values[i]);
+            return -1;
+        }
+
+        fprintf(stderr, "str2ld() parsed value '%s' exactly the same way with strtold(), returned %" LONG_DOUBLE_MODIFIER " vs %" LONG_DOUBLE_MODIFIER "\n", values[i], mine, sys);
+    }
+
+    return 0;
+}
+
+int unit_test_buffer() {
+    BUFFER *wb = buffer_create(1);
+    char string[2048 + 1];
+    char final[9000 + 1];
+    int i;
+
+    for(i = 0; i < 2048; i++)
+        string[i] = (char)((i % 24) + 'a');
+    string[2048] = '\0';
+
+    const char *fmt = "string1: %s\nstring2: %s\nstring3: %s\nstring4: %s";
+    buffer_sprintf(wb, fmt, string, string, string, string);
+    snprintfz(final, 9000, fmt, string, string, string, string);
+
+    const char *s = buffer_tostring(wb);
+
+    if(buffer_strlen(wb) != strlen(final) || strcmp(s, final) != 0) {
+        fprintf(stderr, "\nbuffer_sprintf() is faulty.\n");
+        fprintf(stderr, "\nstring  : %s (length %zu)\n", string, strlen(string));
+        fprintf(stderr, "\nbuffer  : %s (length %zu)\n", s, buffer_strlen(wb));
+        fprintf(stderr, "\nexpected: %s (length %zu)\n", final, strlen(final));
+        buffer_free(wb);
+        return -1;
+    }
+
+    fprintf(stderr, "buffer_sprintf() works as expected.\n");
+    buffer_free(wb);
+    return 0;
+}
+
+// --------------------------------------------------------------------------------------------------------------------
+
+struct feed_values {
+        unsigned long long microseconds;
+        collected_number value;
+};
+
+struct test {
+    char name[100];
+    char description[1024];
+
+    int update_every;
+    unsigned long long multiplier;
+    unsigned long long divisor;
+    RRD_ALGORITHM algorithm;
+
+    unsigned long feed_entries;
+    unsigned long result_entries;
+    struct feed_values *feed;
+    calculated_number *results;
+
+    collected_number *feed2;
+    calculated_number *results2;
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test1
+// test absolute values stored
+
+struct feed_values test1_feed[] = {
+        { 0, 10 },
+        { 1000000, 20 },
+        { 1000000, 30 },
+        { 1000000, 40 },
+        { 1000000, 50 },
+        { 1000000, 60 },
+        { 1000000, 70 },
+        { 1000000, 80 },
+        { 1000000, 90 },
+        { 1000000, 100 },
+};
+
+calculated_number test1_results[] = {
+        20, 30, 40, 50, 60, 70, 80, 90, 100
+};
+
+struct test test1 = {
+        "test1",            // name
+        "test absolute values stored at exactly second boundaries",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_ABSOLUTE,    // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test1_feed,         // feed
+        test1_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test2
+// test absolute values stored in the middle of second boundaries
+
+struct feed_values test2_feed[] = {
+        { 500000, 10 },
+        { 1000000, 20 },
+        { 1000000, 30 },
+        { 1000000, 40 },
+        { 1000000, 50 },
+        { 1000000, 60 },
+        { 1000000, 70 },
+        { 1000000, 80 },
+        { 1000000, 90 },
+        { 1000000, 100 },
+};
+
+calculated_number test2_results[] = {
+        20, 30, 40, 50, 60, 70, 80, 90, 100
+};
+
+struct test test2 = {
+        "test2",            // name
+        "test absolute values stored in the middle of second boundaries",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_ABSOLUTE,    // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test2_feed,         // feed
+        test2_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test3
+
+struct feed_values test3_feed[] = {
+        { 0, 10 },
+        { 1000000, 20 },
+        { 1000000, 30 },
+        { 1000000, 40 },
+        { 1000000, 50 },
+        { 1000000, 60 },
+        { 1000000, 70 },
+        { 1000000, 80 },
+        { 1000000, 90 },
+        { 1000000, 100 },
+};
+
+calculated_number test3_results[] = {
+        10, 10, 10, 10, 10, 10, 10, 10, 10
+};
+
+struct test test3 = {
+        "test3",            // name
+        "test incremental values stored at exactly second boundaries",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test3_feed,         // feed
+        test3_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test4
+
+struct feed_values test4_feed[] = {
+        { 500000, 10 },
+        { 1000000, 20 },
+        { 1000000, 30 },
+        { 1000000, 40 },
+        { 1000000, 50 },
+        { 1000000, 60 },
+        { 1000000, 70 },
+        { 1000000, 80 },
+        { 1000000, 90 },
+        { 1000000, 100 },
+};
+
+calculated_number test4_results[] = {
+        10, 10, 10, 10, 10, 10, 10, 10, 10
+};
+
+struct test test4 = {
+        "test4",            // name
+        "test incremental values stored in the middle of second boundaries",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test4_feed,         // feed
+        test4_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test5
+
+struct feed_values test5_feed[] = {
+        { 500000, 1000 },
+        { 1000000, 2000 },
+        { 1000000, 2000 },
+        { 1000000, 2000 },
+        { 1000000, 3000 },
+        { 1000000, 2000 },
+        { 1000000, 2000 },
+        { 1000000, 2000 },
+        { 1000000, 2000 },
+        { 1000000, 2000 },
+};
+
+calculated_number test5_results[] = {
+        1000, 500, 0, 500, 500, 0, 0, 0, 0
+};
+
+struct test test5 = {
+        "test5",            // name
+        "test incremental values ups and downs",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test5_feed,         // feed
+        test5_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test6
+
+struct feed_values test6_feed[] = {
+        { 250000, 1000 },
+        { 250000, 2000 },
+        { 250000, 3000 },
+        { 250000, 4000 },
+        { 250000, 5000 },
+        { 250000, 6000 },
+        { 250000, 7000 },
+        { 250000, 8000 },
+        { 250000, 9000 },
+        { 250000, 10000 },
+        { 250000, 11000 },
+        { 250000, 12000 },
+        { 250000, 13000 },
+        { 250000, 14000 },
+        { 250000, 15000 },
+        { 250000, 16000 },
+};
+
+calculated_number test6_results[] = {
+        4000, 4000, 4000, 4000
+};
+
+struct test test6 = {
+        "test6",            // name
+        "test incremental values updated within the same second",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        16,                 // feed entries
+        4,                  // result entries
+        test6_feed,         // feed
+        test6_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test7
+
+struct feed_values test7_feed[] = {
+        { 500000, 1000 },
+        { 2000000, 2000 },
+        { 2000000, 3000 },
+        { 2000000, 4000 },
+        { 2000000, 5000 },
+        { 2000000, 6000 },
+        { 2000000, 7000 },
+        { 2000000, 8000 },
+        { 2000000, 9000 },
+        { 2000000, 10000 },
+};
+
+calculated_number test7_results[] = {
+        500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500, 500
+};
+
+struct test test7 = {
+        "test7",            // name
+        "test incremental values updated in long durations",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        18,                 // result entries
+        test7_feed,         // feed
+        test7_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test8
+
+struct feed_values test8_feed[] = {
+        { 500000, 1000 },
+        { 2000000, 2000 },
+        { 2000000, 3000 },
+        { 2000000, 4000 },
+        { 2000000, 5000 },
+        { 2000000, 6000 },
+};
+
+calculated_number test8_results[] = {
+        1250, 2000, 2250, 3000, 3250, 4000, 4250, 5000, 5250, 6000
+};
+
+struct test test8 = {
+        "test8",            // name
+        "test absolute values updated in long durations",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_ABSOLUTE,    // algorithm
+        6,                  // feed entries
+        10,                 // result entries
+        test8_feed,         // feed
+        test8_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test9
+
+struct feed_values test9_feed[] = {
+        { 250000, 1000 },
+        { 250000, 2000 },
+        { 250000, 3000 },
+        { 250000, 4000 },
+        { 250000, 5000 },
+        { 250000, 6000 },
+        { 250000, 7000 },
+        { 250000, 8000 },
+        { 250000, 9000 },
+        { 250000, 10000 },
+        { 250000, 11000 },
+        { 250000, 12000 },
+        { 250000, 13000 },
+        { 250000, 14000 },
+        { 250000, 15000 },
+        { 250000, 16000 },
+};
+
+calculated_number test9_results[] = {
+        4000, 8000, 12000, 16000
+};
+
+struct test test9 = {
+        "test9",            // name
+        "test absolute values updated within the same second",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_ABSOLUTE,    // algorithm
+        16,                 // feed entries
+        4,                  // result entries
+        test9_feed,         // feed
+        test9_results,      // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test10
+
+struct feed_values test10_feed[] = {
+        { 500000,  1000 },
+        { 600000,  1000 +  600 },
+        { 200000,  1600 +  200 },
+        { 1000000, 1800 + 1000 },
+        { 200000,  2800 +  200 },
+        { 2000000, 3000 + 2000 },
+        { 600000,  5000 +  600 },
+        { 400000,  5600 +  400 },
+        { 900000,  6000 +  900 },
+        { 1000000, 6900 + 1000 },
+};
+
+calculated_number test10_results[] = {
+        1000, 1000, 1000, 1000, 1000, 1000, 1000
+};
+
+struct test test10 = {
+        "test10",           // name
+        "test incremental values updated in short and long durations",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        7,                  // result entries
+        test10_feed,        // feed
+        test10_results,     // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test11
+
+struct feed_values test11_feed[] = {
+        { 0, 10 },
+        { 1000000, 20 },
+        { 1000000, 30 },
+        { 1000000, 40 },
+        { 1000000, 50 },
+        { 1000000, 60 },
+        { 1000000, 70 },
+        { 1000000, 80 },
+        { 1000000, 90 },
+        { 1000000, 100 },
+};
+
+collected_number test11_feed2[] = {
+    10, 20, 30, 40, 50, 60, 70, 80, 90, 100
+};
+
+calculated_number test11_results[] = {
+        50, 50, 50, 50, 50, 50, 50, 50, 50
+};
+
+calculated_number test11_results2[] = {
+        50, 50, 50, 50, 50, 50, 50, 50, 50
+};
+
+struct test test11 = {
+        "test11",           // name
+        "test percentage-of-incremental-row with equal values",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_PCENT_OVER_DIFF_TOTAL,   // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test11_feed,        // feed
+        test11_results,     // results
+        test11_feed2,       // feed2
+        test11_results2     // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test12
+
+struct feed_values test12_feed[] = {
+        { 0, 10 },
+        { 1000000, 20 },
+        { 1000000, 30 },
+        { 1000000, 40 },
+        { 1000000, 50 },
+        { 1000000, 60 },
+        { 1000000, 70 },
+        { 1000000, 80 },
+        { 1000000, 90 },
+        { 1000000, 100 },
+};
+
+collected_number test12_feed2[] = {
+    10*3, 20*3, 30*3, 40*3, 50*3, 60*3, 70*3, 80*3, 90*3, 100*3
+};
+
+calculated_number test12_results[] = {
+        25, 25, 25, 25, 25, 25, 25, 25, 25
+};
+
+calculated_number test12_results2[] = {
+        75, 75, 75, 75, 75, 75, 75, 75, 75
+};
+
+struct test test12 = {
+        "test12",           // name
+        "test percentage-of-incremental-row with equal values",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_PCENT_OVER_DIFF_TOTAL,   // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test12_feed,        // feed
+        test12_results,     // results
+        test12_feed2,       // feed2
+        test12_results2     // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test13
+
+struct feed_values test13_feed[] = {
+        { 500000,  1000 },
+        { 600000,  1000 +  600 },
+        { 200000,  1600 +  200 },
+        { 1000000, 1800 + 1000 },
+        { 200000,  2800 +  200 },
+        { 2000000, 3000 + 2000 },
+        { 600000,  5000 +  600 },
+        { 400000,  5600 +  400 },
+        { 900000,  6000 +  900 },
+        { 1000000, 6900 + 1000 },
+};
+
+calculated_number test13_results[] = {
+        83.3333300, 100, 100, 100, 100, 100, 100
+};
+
+struct test test13 = {
+        "test13",           // name
+        "test incremental values updated in short and long durations",
+        1,                  // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_PCENT_OVER_DIFF_TOTAL,   // algorithm
+        10,                 // feed entries
+        7,                  // result entries
+        test13_feed,        // feed
+        test13_results,     // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test14
+
+struct feed_values test14_feed[] = {
+        {        0, 0x015397dc42151c41ULL },
+        { 13573000, 0x015397e612e3ff5dULL },
+        { 29969000, 0x015397f905ecdaa8ULL },
+        { 29958000, 0x0153980c2a6cb5e4ULL },
+        { 30054000, 0x0153981f4032fb83ULL },
+        { 34952000, 0x015398355efadaccULL },
+        { 25046000, 0x01539845ba4b09f8ULL },
+        { 29947000, 0x0153985948bf381dULL },
+        { 30054000, 0x0153986c5b9c27e2ULL },
+        { 29942000, 0x0153987f888982d0ULL },
+};
+
+calculated_number test14_results[] = {
+        23.1383300, 21.8515600, 21.8804600, 21.7788000, 22.0112200, 22.4386100, 22.0906100, 21.9150800
+};
+
+struct test test14 = {
+        "test14",            // name
+        "issue #981 with real data",
+        30,                 // update_every
+        8,                  // multiplier
+        1000000000,         // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        8,                  // result entries
+        test14_feed,        // feed
+        test14_results,     // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+struct feed_values test14b_feed[] = {
+        {        0, 0 },
+        { 13573000, 13573000 },
+        { 29969000, 13573000 + 29969000 },
+        { 29958000, 13573000 + 29969000 + 29958000 },
+        { 30054000, 13573000 + 29969000 + 29958000 + 30054000 },
+        { 34952000, 13573000 + 29969000 + 29958000 + 30054000 + 34952000 },
+        { 25046000, 13573000 + 29969000 + 29958000 + 30054000 + 34952000 + 25046000 },
+        { 29947000, 13573000 + 29969000 + 29958000 + 30054000 + 34952000 + 25046000 + 29947000 },
+        { 30054000, 13573000 + 29969000 + 29958000 + 30054000 + 34952000 + 25046000 + 29947000 + 30054000 },
+        { 29942000, 13573000 + 29969000 + 29958000 + 30054000 + 34952000 + 25046000 + 29947000 + 30054000 + 29942000 },
+};
+
+calculated_number test14b_results[] = {
+        1000000, 1000000, 1000000, 1000000, 1000000, 1000000, 1000000, 1000000
+};
+
+struct test test14b = {
+        "test14b",            // name
+        "issue #981 with dummy data",
+        30,                 // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        8,                  // result entries
+        test14b_feed,        // feed
+        test14b_results,     // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+struct feed_values test14c_feed[] = {
+        { 29000000, 29000000 },
+        {  1000000, 29000000 + 1000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 + 30000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 },
+        { 30000000, 29000000 + 1000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 + 30000000 },
+};
+
+calculated_number test14c_results[] = {
+        1000000, 1000000, 1000000, 1000000, 1000000, 1000000, 1000000, 1000000, 1000000
+};
+
+struct test test14c = {
+        "test14c",            // name
+        "issue #981 with dummy data, checking for late start",
+        30,                 // update_every
+        1,                  // multiplier
+        1,                  // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test14c_feed,        // feed
+        test14c_results,     // results
+        NULL,               // feed2
+        NULL                // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+// test15
+
+struct feed_values test15_feed[] = {
+        {       0, 1068066388 },
+        { 1008752, 1068822698 },
+        {  993809, 1069573072 },
+        {  995911, 1070324135 },
+        { 1014562, 1071078166 },
+        {  994684, 1071831349 },
+        {  993128, 1072235739 },
+        { 1010332, 1072958871 },
+        { 1003394, 1073707019 },
+        {  995201, 1074460255 },
+};
+
+collected_number test15_feed2[] = {
+    178825286, 178825286, 178825286, 178825286, 178825498, 178825498, 179165652, 179202964, 179203282, 179204130
+};
+
+calculated_number test15_results[] = {
+        5857.4080000, 5898.4540000, 5891.6590000, 5806.3160000, 5914.2640000, 3202.2630000, 5589.6560000, 5822.5260000, 5911.7520000
+};
+
+calculated_number test15_results2[] = {
+        0.0000000, 0.0000000, 0.0024944, 1.6324779, 0.0212777, 2655.1890000, 290.5387000, 5.6733610, 6.5960220
+};
+
+struct test test15 = {
+        "test15",           // name
+        "test incremental with 2 dimensions",
+        1,                  // update_every
+        8,                  // multiplier
+        1024,               // divisor
+        RRD_ALGORITHM_INCREMENTAL, // algorithm
+        10,                 // feed entries
+        9,                  // result entries
+        test15_feed,        // feed
+        test15_results,     // results
+        test15_feed2,       // feed2
+        test15_results2     // results2
+};
+
+// --------------------------------------------------------------------------------------------------------------------
+
+int run_test(struct test *test)
+{
+    fprintf(stderr, "\nRunning test '%s':\n%s\n", test->name, test->description);
+
+    default_rrd_memory_mode = RRD_MEMORY_MODE_ALLOC;
+    default_rrd_update_every = test->update_every;
+
+    char name[101];
+    snprintfz(name, 100, "unittest-%s", test->name);
+
+    // create the chart
+    RRDSET *st = rrdset_create_localhost("netdata", name, name, "netdata", NULL, "Unit Testing", "a value", "unittest", NULL, 1
+                                         , test->update_every, RRDSET_TYPE_LINE);
+    RRDDIM *rd = rrddim_add(st, "dim1", NULL, test->multiplier, test->divisor, test->algorithm);
+    
+    RRDDIM *rd2 = NULL;
+    if(test->feed2)
+        rd2 = rrddim_add(st, "dim2", NULL, test->multiplier, test->divisor, test->algorithm);
+
+    rrdset_flag_set(st, RRDSET_FLAG_DEBUG);
+
+    // feed it with the test data
+    time_t time_now = 0, time_start = now_realtime_sec();
+    unsigned long c;
+    collected_number last = 0;
+    for(c = 0; c < test->feed_entries; c++) {
+        if(debug_flags) fprintf(stderr, "\n\n");
+
+        if(c) {
+            time_now += test->feed[c].microseconds;
+            fprintf(stderr, "    > %s: feeding position %lu, after %0.3f seconds (%0.3f seconds from start), delta " CALCULATED_NUMBER_FORMAT ", rate " CALCULATED_NUMBER_FORMAT "\n", 
+                test->name, c+1,
+                (float)test->feed[c].microseconds / 1000000.0,
+                (float)time_now / 1000000.0,
+                ((calculated_number)test->feed[c].value - (calculated_number)last) * (calculated_number)test->multiplier / (calculated_number)test->divisor,
+                (((calculated_number)test->feed[c].value - (calculated_number)last) * (calculated_number)test->multiplier / (calculated_number)test->divisor) / (calculated_number)test->feed[c].microseconds * (calculated_number)1000000);
+
+            // rrdset_next_usec_unfiltered(st, test->feed[c].microseconds);
+            st->usec_since_last_update = test->feed[c].microseconds;
+        }
+        else {
+            fprintf(stderr, "    > %s: feeding position %lu\n", test->name, c+1);
+        }
+
+        fprintf(stderr, "       >> %s with value " COLLECTED_NUMBER_FORMAT "\n", rd->name, test->feed[c].value);
+        rrddim_set(st, "dim1", test->feed[c].value);
+        last = test->feed[c].value;
+
+        if(rd2) {
+            fprintf(stderr, "       >> %s with value " COLLECTED_NUMBER_FORMAT "\n", rd2->name, test->feed2[c]);
+            rrddim_set(st, "dim2", test->feed2[c]);
+        }
+
+        rrdset_done(st);
+
+        // align the first entry to second boundary
+        if(!c) {
+            fprintf(stderr, "    > %s: fixing first collection time to be %llu microseconds to second boundary\n", test->name, test->feed[c].microseconds);
+            rd->last_collected_time.tv_usec = st->last_collected_time.tv_usec = st->last_updated.tv_usec = test->feed[c].microseconds;
+            // time_start = st->last_collected_time.tv_sec;
+        }
+    }
+
+    // check the result
+    int errors = 0;
+
+    if(st->counter != test->result_entries) {
+        fprintf(stderr, "    %s stored %zu entries, but we were expecting %lu, ### E R R O R ###\n", test->name, st->counter, test->result_entries);
+        errors++;
+    }
+
+    unsigned long max = (st->counter < test->result_entries)?st->counter:test->result_entries;
+    for(c = 0 ; c < max ; c++) {
+        calculated_number v = unpack_storage_number(rd->values[c]);
+        calculated_number n = test->results[c];
+        int same = (calculated_number_round(v * 10000000.0) == calculated_number_round(n * 10000000.0))?1:0;
+        fprintf(stderr, "    %s/%s: checking position %lu (at %lu secs), expecting value " CALCULATED_NUMBER_FORMAT ", found " CALCULATED_NUMBER_FORMAT ", %s\n",
+            test->name, rd->name, c+1,
+            (rrdset_first_entry_t(st) + c * st->update_every) - time_start,
+            n, v, (same)?"OK":"### E R R O R ###");
+
+        if(!same) errors++;
+
+        if(rd2) {
+            v = unpack_storage_number(rd2->values[c]);
+            n = test->results2[c];
+            same = (calculated_number_round(v * 10000000.0) == calculated_number_round(n * 10000000.0))?1:0;
+            fprintf(stderr, "    %s/%s: checking position %lu (at %lu secs), expecting value " CALCULATED_NUMBER_FORMAT ", found " CALCULATED_NUMBER_FORMAT ", %s\n",
+                test->name, rd2->name, c+1,
+                (rrdset_first_entry_t(st) + c * st->update_every) - time_start,
+                n, v, (same)?"OK":"### E R R O R ###");
+            if(!same) errors++;
+        }
+    }
+
+    return errors;
+}
+
+static int test_variable_renames(void) {
+    fprintf(stderr, "Creating chart\n");
+    RRDSET *st = rrdset_create_localhost("chart", "ID", NULL, "family", "context", "Unit Testing", "a value", "unittest", NULL, 1, 1, RRDSET_TYPE_LINE);
+    fprintf(stderr, "Created chart with id '%s', name '%s'\n", st->id, st->name);
+
+    fprintf(stderr, "Creating dimension DIM1\n");
+    RRDDIM *rd1 = rrddim_add(st, "DIM1", NULL, 1, 1, RRD_ALGORITHM_INCREMENTAL);
+    fprintf(stderr, "Created dimension with id '%s', name '%s'\n", rd1->id, rd1->name);
+
+    fprintf(stderr, "Creating dimension DIM2\n");
+    RRDDIM *rd2 = rrddim_add(st, "DIM2", NULL, 1, 1, RRD_ALGORITHM_INCREMENTAL);
+    fprintf(stderr, "Created dimension with id '%s', name '%s'\n", rd2->id, rd2->name);
+
+    fprintf(stderr, "Renaming chart to CHARTNAME1\n");
+    rrdset_set_name(st, "CHARTNAME1");
+    fprintf(stderr, "Renamed chart with id '%s' to name '%s'\n", st->id, st->name);
+
+    fprintf(stderr, "Renaming chart to CHARTNAME2\n");
+    rrdset_set_name(st, "CHARTNAME2");
+    fprintf(stderr, "Renamed chart with id '%s' to name '%s'\n", st->id, st->name);
+
+    fprintf(stderr, "Renaming dimension DIM1 to DIM1NAME1\n");
+    rrddim_set_name(st, rd1, "DIM1NAME1");
+    fprintf(stderr, "Renamed dimension with id '%s' to name '%s'\n", rd1->id, rd1->name);
+
+    fprintf(stderr, "Renaming dimension DIM1 to DIM1NAME2\n");
+    rrddim_set_name(st, rd1, "DIM1NAME2");
+    fprintf(stderr, "Renamed dimension with id '%s' to name '%s'\n", rd1->id, rd1->name);
+
+    fprintf(stderr, "Renaming dimension DIM2 to DIM2NAME1\n");
+    rrddim_set_name(st, rd2, "DIM2NAME1");
+    fprintf(stderr, "Renamed dimension with id '%s' to name '%s'\n", rd2->id, rd2->name);
+
+    fprintf(stderr, "Renaming dimension DIM2 to DIM2NAME2\n");
+    rrddim_set_name(st, rd2, "DIM2NAME2");
+    fprintf(stderr, "Renamed dimension with id '%s' to name '%s'\n", rd2->id, rd2->name);
+
+    BUFFER *buf = buffer_create(1);
+    health_api_v1_chart_variables2json(st, buf);
+    fprintf(stderr, "%s", buffer_tostring(buf));
+    buffer_free(buf);
+    return 1;
+}
+
+int check_strdupz_path_subpath() {
+
+    struct strdupz_path_subpath_checks {
+        const char *path;
+        const char *subpath;
+        const char *result;
+    } checks[] = {
+            { "",                "",            "."                     },
+            { "/",               "",            "/"                     },
+            { "/etc/netdata",    "",            "/etc/netdata"          },
+            { "/etc/netdata///", "",            "/etc/netdata"          },
+            { "/etc/netdata///", "health.d",    "/etc/netdata/health.d" },
+            { "/etc/netdata///", "///health.d", "/etc/netdata/health.d" },
+            { "/etc/netdata",    "///health.d", "/etc/netdata/health.d" },
+            { "",                "///health.d", "./health.d"            },
+            { "/",               "///health.d", "/health.d"             },
+
+            // terminator
+            { NULL, NULL, NULL }
+    };
+
+    size_t i;
+    for(i = 0; checks[i].result ; i++) {
+        char *s = strdupz_path_subpath(checks[i].path, checks[i].subpath);
+        fprintf(stderr, "strdupz_path_subpath(\"%s\", \"%s\") = \"%s\": ", checks[i].path, checks[i].subpath, s);
+        if(!s || strcmp(s, checks[i].result) != 0) {
+            freez(s);
+            fprintf(stderr, "FAILED\n");
+            return 1;
+        }
+        else {
+            freez(s);
+            fprintf(stderr, "OK\n");
+        }
+    }
+
+    return 0;
+}
+
+int run_all_mockup_tests(void)
+{
+    if(check_strdupz_path_subpath())
+        return 1;
+
+    if(check_number_printing())
+        return 1;
+
+    if(check_rrdcalc_comparisons())
+        return 1;
+
+    if(!test_variable_renames())
+        return 1;
+
+    if(run_test(&test1))
+        return 1;
+
+    if(run_test(&test2))
+        return 1;
+
+    if(run_test(&test3))
+        return 1;
+
+    if(run_test(&test4))
+        return 1;
+
+    if(run_test(&test5))
+        return 1;
+
+    if(run_test(&test6))
+        return 1;
+
+    if(run_test(&test7))
+        return 1;
+
+    if(run_test(&test8))
+        return 1;
+
+    if(run_test(&test9))
+        return 1;
+
+    if(run_test(&test10))
+        return 1;
+
+    if(run_test(&test11))
+        return 1;
+
+    if(run_test(&test12))
+        return 1;
+
+    if(run_test(&test13))
+        return 1;
+
+    if(run_test(&test14))
+        return 1;
+
+    if(run_test(&test14b))
+        return 1;
+
+    if(run_test(&test14c))
+        return 1;
+
+    if(run_test(&test15))
+        return 1;
+
+
+
+    return 0;
+}
+
+int unit_test(long delay, long shift)
+{
+    static int repeat = 0;
+    repeat++;
+
+    char name[101];
+    snprintfz(name, 100, "unittest-%d-%ld-%ld", repeat, delay, shift);
+
+    //debug_flags = 0xffffffff;
+    default_rrd_memory_mode = RRD_MEMORY_MODE_ALLOC;
+    default_rrd_update_every = 1;
+
+    int do_abs = 1;
+    int do_inc = 1;
+    int do_abst = 0;
+    int do_absi = 0;
+
+    RRDSET *st = rrdset_create_localhost("netdata", name, name, "netdata", NULL, "Unit Testing", "a value", "unittest", NULL, 1, 1
+                                         , RRDSET_TYPE_LINE);
+    rrdset_flag_set(st, RRDSET_FLAG_DEBUG);
+
+    RRDDIM *rdabs = NULL;
+    RRDDIM *rdinc = NULL;
+    RRDDIM *rdabst = NULL;
+    RRDDIM *rdabsi = NULL;
+
+    if(do_abs) rdabs = rrddim_add(st, "absolute", "absolute", 1, 1, RRD_ALGORITHM_ABSOLUTE);
+    if(do_inc) rdinc = rrddim_add(st, "incremental", "incremental", 1, 1, RRD_ALGORITHM_INCREMENTAL);
+    if(do_abst) rdabst = rrddim_add(st, "percentage-of-absolute-row", "percentage-of-absolute-row", 1, 1, RRD_ALGORITHM_PCENT_OVER_ROW_TOTAL);
+    if(do_absi) rdabsi = rrddim_add(st, "percentage-of-incremental-row", "percentage-of-incremental-row", 1, 1, RRD_ALGORITHM_PCENT_OVER_DIFF_TOTAL);
+
+    long increment = 1000;
+    collected_number i = 0;
+
+    unsigned long c, dimensions = 0;
+    RRDDIM *rd;
+    for(rd = st->dimensions ; rd ; rd = rd->next) dimensions++;
+
+    for(c = 0; c < 20 ;c++) {
+        i += increment;
+
+        fprintf(stderr, "\n\nLOOP = %lu, DELAY = %ld, VALUE = " COLLECTED_NUMBER_FORMAT "\n", c, delay, i);
+        if(c) {
+            // rrdset_next_usec_unfiltered(st, delay);
+            st->usec_since_last_update = delay;
+        }
+        if(do_abs) rrddim_set(st, "absolute", i);
+        if(do_inc) rrddim_set(st, "incremental", i);
+        if(do_abst) rrddim_set(st, "percentage-of-absolute-row", i);
+        if(do_absi) rrddim_set(st, "percentage-of-incremental-row", i);
+
+        if(!c) {
+            now_realtime_timeval(&st->last_collected_time);
+            st->last_collected_time.tv_usec = shift;
+        }
+
+        // prevent it from deleting the dimensions
+        for(rd = st->dimensions ; rd ; rd = rd->next)
+            rd->last_collected_time.tv_sec = st->last_collected_time.tv_sec;
+
+        rrdset_done(st);
+    }
+
+    unsigned long oincrement = increment;
+    increment = increment * st->update_every * 1000000 / delay;
+    fprintf(stderr, "\n\nORIGINAL INCREMENT: %lu, INCREMENT %ld, DELAY %ld, SHIFT %ld\n", oincrement * 10, increment * 10, delay, shift);
+
+    int ret = 0;
+    storage_number sn;
+    calculated_number cn, v;
+    for(c = 0 ; c < st->counter ; c++) {
+        fprintf(stderr, "\nPOSITION: c = %lu, EXPECTED VALUE %lu\n", c, (oincrement + c * increment + increment * (1000000 - shift) / 1000000 )* 10);
+
+        for(rd = st->dimensions ; rd ; rd = rd->next) {
+            sn = rd->values[c];
+            cn = unpack_storage_number(sn);
+            fprintf(stderr, "\t %s " CALCULATED_NUMBER_FORMAT " (PACKED AS " STORAGE_NUMBER_FORMAT ")   ->   ", rd->id, cn, sn);
+
+            if(rd == rdabs) v =
+                (     oincrement
+                    // + (increment * (1000000 - shift) / 1000000)
+                    + (c + 1) * increment
+                );
+
+            else if(rd == rdinc) v = (c?(increment):(increment * (1000000 - shift) / 1000000));
+            else if(rd == rdabst) v = oincrement / dimensions / 10;
+            else if(rd == rdabsi) v = oincrement / dimensions / 10;
+            else v = 0;
+
+            if(v == cn) fprintf(stderr, "passed.\n");
+            else {
+                fprintf(stderr, "ERROR! (expected " CALCULATED_NUMBER_FORMAT ")\n", v);
+                ret = 1;
+            }
+        }
+    }
+
+    if(ret)
+        fprintf(stderr, "\n\nUNIT TEST(%ld, %ld) FAILED\n\n", delay, shift);
+
+    return ret;
+}