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diff --git a/man/slabtop.1 b/man/slabtop.1 new file mode 100644 index 0000000..0734348 --- /dev/null +++ b/man/slabtop.1 @@ -0,0 +1,123 @@ +.\" +.\" Copyright (c) 2011-2023 Craig Small <csmall@dropbear.xyz> +.\" Copyright (c) 2013-2023 Jim Warner <james.warner@comcast.net> +.\" Copyright (c) 2011-2012 Sami Kerola <kerolasa@iki.fi> +.\" Copyright (c) 2004-2006 Albert Cahalan +.\" Copyright (C) 2003 Chris Rivera +.\" +.\" This program is free software; you can redistribute it and/or modify +.\" it under the terms of the GNU Lesser General Public License as +.\" published by the Free Software Foundation; either version 2.1 of the +.\" License, or (at your option) any later version. +.\" +.\" +.TH SLABTOP "1" "2021-03-11" "procps-ng" "User Commands" +.SH NAME +slabtop \- display kernel slab cache information in real time +.SH SYNOPSIS +.B slabtop +[\fIoptions\fR] +.SH DESCRIPTION +.B slabtop +displays detailed kernel slab cache information in real time. It displays a +listing of the top caches sorted by one of the listed sort criteria. It also +displays a statistics header filled with slab layer information. +.SH OPTIONS +Normal invocation of +.B slabtop +does not require any options. The behavior, however, can be fine-tuned by +specifying one or more of the following flags: +.TP +\fB\-d\fR, \fB\-\-delay\fR=\fIN\fR +Refresh the display every +.I n +in seconds. By default, +.B slabtop +refreshes the display every three seconds. To exit the program, hit +.BR q . +This cannot be combined with the \fB-o\fR option. +.TP +\fB\-s\fR, \fB\-\-sort\fR=\fIS\fR +Sort by \fIS\fR, where \fIS\fR is one of the sort criteria. +.TP +\fB\-o\fR, \fB\-\-once\fR +Display the output once and then exit. +.TP +\fB\-V\fR, \fB\-\-version\fR +Display version information and exit. +.TP +\fB\-h\fR, \fB\-\-help\fR +Display usage information and exit. +.SH SORT CRITERIA +The following are valid sort criteria used to sort the individual slab caches +and thereby determine what are the "top" slab caches to display. The default +sort criteria is to sort by the number of objects ("o"). +.PP +The sort criteria can also be changed while +.B slabtop +is running by pressing the associated character. +.TS +l l l. +\fBcharacter description header\fR +a number of active objects ACTIVE +b objects per slab OBJ/SLAB +c cache size CACHE SIZE +l number of slabs SLABS +v number of active slabs N/A +n name NAME\: +o number of objects OBJS +p pages per slab N/A +s object size OBJ SIZE +u cache utilization USE +.TE +.SH COMMANDS +.B slabtop +accepts keyboard commands from the user during use. The following are +supported. In the case of letters, both cases are accepted. +.PP +Each of the valid sort characters are also accepted, to change the sort +routine. See the section +.BR "SORT CRITERIA" . +.TP +.BR <SPACEBAR> +Refresh the screen. +.TP +.BR Q +Quit the program. +.SH FILES +.TP +.I /proc/slabinfo +slab information +.SH "SEE ALSO" +.BR free (1), +.BR ps (1), +.BR top (1), +.BR vmstat (8) +.SH NOTES +Currently, +.B slabtop +requires a 2.4 or later kernel (specifically, a version 1.1 or later +.IR /proc/slabinfo ). +Kernel 2.2 should be supported in the future. +.PP +The +.B slabtop +statistic header is tracking how many bytes of slabs are being +used and is not a measure of physical memory. The 'Slab' field in the +\fI/proc/meminfo\fR file is tracking information about used slab physical memory. +.PP +The +.B CACHE SIZE +column is not accurate, it's the upper limit of memory used by specific slab. When system +using slub (most common case) is under high memory pressure, there are slab order +fallbacks, which means "pages per slab" is not constant and may decrease. +.SH AUTHORS +Written by Chris Rivera and Robert Love. +.PP +.B slabtop +was inspired by Martin Bligh's perl script, +.BR vmtop . +.SH "REPORTING BUGS" +Please send bug reports to +.UR procps@freelists.org +.UE |