diff options
Diffstat (limited to 'man2/swapon.2')
| -rw-r--r-- | man2/swapon.2 | 29 |
1 files changed, 17 insertions, 12 deletions
diff --git a/man2/swapon.2 b/man2/swapon.2 index 400f609..87bd6a0 100644 --- a/man2/swapon.2 +++ b/man2/swapon.2 @@ -22,7 +22,7 @@ .\" Author: Rafael Aquini <aquini@redhat.com> .\" Date: Wed Jul 3 15:02:46 2013 -0700 .\" -.TH swapon 2 2023-03-30 "Linux man-pages 6.05.01" +.TH swapon 2 2023-12-22 "Linux man-pages 6.7" .SH NAME swapon, swapoff \- start/stop swapping to file/device .SH LIBRARY @@ -31,7 +31,7 @@ Standard C library .SH SYNOPSIS .nf .B #include <sys/swap.h> -.PP +.P .BI "int swapon(const char *" path ", int " swapflags ); .BI "int swapoff(const char *" path ); .fi @@ -42,7 +42,7 @@ sets the swap area to the file or block device specified by .BR swapoff () stops swapping to the file or block device specified by .IR path . -.PP +.P If the .B SWAP_FLAG_PREFER flag is specified in the @@ -52,13 +52,13 @@ argument, the new swap area will have a higher priority than default. The priority is encoded within .I swapflags as: -.PP +.P .in +4n .EX .I "(prio << SWAP_FLAG_PRIO_SHIFT) & SWAP_FLAG_PRIO_MASK" .EE .in -.PP +.P If the .B SWAP_FLAG_DISCARD flag is specified in the @@ -69,7 +69,7 @@ if the swap device supports the discard or trim operation. (This may improve performance on some Solid State Devices, but often it does not.) See also NOTES. -.PP +.P These functions may be used only by a privileged process (one having the .B CAP_SYS_ADMIN capability). @@ -78,13 +78,13 @@ Each swap area has a priority, either high or low. The default priority is low. Within the low-priority areas, newer areas are even lower priority than older areas. -.PP +.P All priorities set with .I swapflags are high-priority, higher than default. They may have any nonnegative value chosen by the caller. Higher numbers mean higher priority. -.PP +.P Swap pages are allocated from areas in priority order, highest priority first. For areas with different priorities, @@ -92,7 +92,7 @@ a higher-priority area is exhausted before using a lower-priority area. If two or more areas have the same priority, and it is the highest priority available, pages are allocated on a round-robin basis between them. -.PP +.P As of Linux 1.3.6, the kernel usually follows these rules, but there are exceptions. .SH RETURN VALUE @@ -156,7 +156,7 @@ argument was introduced in Linux 1.3.2. .SH NOTES The partition or path must be prepared with .BR mkswap (8). -.PP +.P There is an upper limit on the number of swap files that may be used, defined by the kernel constant .BR MAX_SWAPFILES . @@ -164,7 +164,8 @@ Before Linux 2.4.10, .B MAX_SWAPFILES has the value 8; since Linux 2.4.10, it has the value 32. -Since Linux 2.6.18, the limit is decreased by 2 (thus: 30) +Since Linux 2.6.18, the limit is decreased by 2 (thus 30), +since Linux 5.19, the limit is decreased by 3 (thus: 29) if the kernel is built with the .B CONFIG_MIGRATION option @@ -180,7 +181,11 @@ Since Linux 5.14, the limit is further decreased by 4 if the kernel is built with the .B CONFIG_DEVICE_PRIVATE option. -.PP +Since Linux 5.19, the limit is further decreased by 1 +if the kernel is built with the +.B CONFIG_PTE_MARKER +option. +.P Discard of swap pages was introduced in Linux 2.6.29, then made conditional on the |