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diff --git a/man5/slabinfo.5 b/man5/slabinfo.5 deleted file mode 100644 index c3121fa28..000000000 --- a/man5/slabinfo.5 +++ /dev/null @@ -1,220 +0,0 @@ -.\" Copyright (c) 2001 Andreas Dilger (adilger@turbolinux.com) -.\" and Copyright (c) 2017 Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH slabinfo 5 (date) "Linux man-pages (unreleased)" -.SH NAME -slabinfo \- kernel slab allocator statistics -.SH SYNOPSIS -.nf -.B cat /proc/slabinfo -.fi -.SH DESCRIPTION -Frequently used objects in the Linux kernel -(buffer heads, inodes, dentries, etc.) -have their own cache. -The file -.I /proc/slabinfo -gives statistics on these caches. -The following (edited) output shows an example of the -contents of this file: -.P -.EX -$ \fBsudo cat /proc/slabinfo\fP -slabinfo \- version: 2.1 -# name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab> ... -sigqueue 100 100 160 25 1 : tunables 0 0 0 : slabdata 4 4 0 -sighand_cache 355 405 2112 15 8 : tunables 0 0 0 : slabdata 27 27 0 -kmalloc\-8192 96 96 8192 4 8 : tunables 0 0 0 : slabdata 24 24 0 -\&... -.EE -.P -The first line of output includes a version number, -which allows an application that is reading the file to handle changes -in the file format. -(See VERSIONS, below.) -The next line lists the names of the columns in the remaining lines. -.P -Each of the remaining lines displays information about a specified cache. -Following the cache name, -the output shown in each line shows three components for each cache: -.IP \[bu] 3 -statistics -.IP \[bu] -tunables -.IP \[bu] -slabdata -.P -The statistics are as follows: -.TP -.I active_objs -The number of objects that are currently active (i.e., in use). -.TP -.I num_objs -The total number of allocated objects -(i.e., objects that are both in use and not in use). -.TP -.I objsize -The size of objects in this slab, in bytes. -.TP -.I objperslab -The number of objects stored in each slab. -.TP -.I pagesperslab -The number of pages allocated for each slab. -.P -The -.I tunables -entries in each line show tunable parameters for the corresponding cache. -When using the default SLUB allocator, there are no tunables, the -.I /proc/slabinfo -file is not writable, and the value 0 is shown in these fields. -When using the older SLAB allocator, -the tunables for a particular cache can be set by writing -lines of the following form to -.IR /proc/slabinfo : -.P -.in +4n -.EX -# \fBecho \[aq]name limit batchcount sharedfactor\[aq] > /proc/slabinfo\fP -.EE -.in -.P -Here, -.I name -is the cache name, and -.IR limit , -.IR batchcount , -and -.I sharedfactor -are integers defining new values for the corresponding tunables. -The -.I limit -value should be a positive value, -.I batchcount -should be a positive value that is less than or equal to -.IR limit , -and -.I sharedfactor -should be nonnegative. -If any of the specified values is invalid, -the cache settings are left unchanged. -.P -The -.I tunables -entries in each line contain the following fields: -.TP -.I limit -The maximum number of objects that will be cached. -.\" https://lwn.net/Articles/56360/ -.\" This is the limit on the number of free objects that can be stored -.\" in the per-CPU free list for this slab cache. -.TP -.I batchcount -On SMP systems, this specifies the number of objects to transfer at one time -when refilling the available object list. -.\" https://lwn.net/Articles/56360/ -.\" On SMP systems, when we refill the available object list, instead -.\" of doing one object at a time, we do batch-count objects at a time. -.TP -.I sharedfactor -[To be documented] -.\" -.P -The -.I slabdata -entries in each line contain the following fields: -.TP -.I active_slabs -The number of active slabs. -.TP -.I nums_slabs -The total number of slabs. -.TP -.I sharedavail -[To be documented] -.P -Note that because of object alignment and slab cache overhead, -objects are not normally packed tightly into pages. -Pages with even one in-use object are considered in-use and cannot be -freed. -.P -Kernels configured with -.B CONFIG_DEBUG_SLAB -will also have additional statistics fields in each line, -and the first line of the file will contain the string "(statistics)". -The statistics field include : the high water mark of active -objects; the number of times objects have been allocated; -the number of times the cache has grown (new pages added -to this cache); the number of times the cache has been -reaped (unused pages removed from this cache); and the -number of times there was an error allocating new pages -to this cache. -.\" -.\" SMP systems will also have "(SMP)" in the first line of -.\" output, and will have two additional columns for each slab, -.\" reporting the slab allocation policy for the CPU-local -.\" cache (to reduce the need for inter-CPU synchronization -.\" when allocating objects from the cache). -.\" The first column is the per-CPU limit: the maximum number of objects that -.\" will be cached for each CPU. -.\" The second column is the -.\" batchcount: the maximum number of free objects in the -.\" global cache that will be transferred to the per-CPU cache -.\" if it is empty, or the number of objects to be returned -.\" to the global cache if the per-CPU cache is full. -.\" -.\" If both slab cache statistics and SMP are defined, there -.\" will be four additional columns, reporting the per-CPU -.\" cache statistics. -.\" The first two are the per-CPU cache -.\" allocation hit and miss counts: the number of times an -.\" object was or was not available in the per-CPU cache -.\" for allocation. -.\" The next two are the per-CPU cache free -.\" hit and miss counts: the number of times a freed object -.\" could or could not fit within the per-CPU cache limit, -.\" before flushing objects to the global cache. -.SH VERSIONS -The -.I /proc/slabinfo -file first appeared in Linux 2.1.23. -The file is versioned, -and over time there have been a number of versions with different layouts: -.TP -1.0 -Present throughout the Linux 2.2.x kernel series. -.TP -1.1 -Present in the Linux 2.4.x kernel series. -.\" First appeared in Linux 2.4.0-test3 -.TP -1.2 -A format that was briefly present in the Linux 2.5 development series. -.\" from Linux 2.5.45 to Linux 2.5.70 -.TP -2.0 -Present in Linux 2.6.x kernels up to and including Linux 2.6.9. -.\" First appeared in Linux 2.5.71 -.TP -2.1 -The current format, which first appeared in Linux 2.6.10. -.SH NOTES -Only root can read and (if the kernel was configured with -.BR CONFIG_SLAB ) -write the -.I /proc/slabinfo -file. -.P -The total amount of memory allocated to the SLAB/SLUB cache is shown in the -.I Slab -field of -.IR /proc/meminfo . -.SH SEE ALSO -.BR slabtop (1) -.P -The kernel source file -.I Documentation/vm/slub.txt -and -.IR tools/vm/slabinfo.c . |