Command line and full screen utilities for browsing procfs, a "pseudo" file system dynamically generated by Linux to provide information about the status of entries in its process table.
dae897b54d
While the kernel calls the fields pgpgin and pgpgout, the units here are not pages, but KiB (or 2x 512 sectors). The comments come from the referenced merged request, this commit fixes the "vmstat -s lies" part: https://elixir.bootlin.com/linux/v5.15-rc7/source/block/blk-core.c#L1057 has submit_bio() which includes the count_vm_events(PGPGIN, count) but what is count? it is usually what bio_sectors() returns. bio_sectors() is a macro in https://elixir.bootlin.com/linux/v5.15-rc7/source/include/linux/bio.h#L49 that defines that as bio->bi_iter.bi_size >> 9. 2^9 is 512 or the sector size. So our count is incremented by the number of 512-byte sectors. As @dublio has already pointed out before this result is printed to vmstat, it is /= 2 to give the number of kibibytes (as the sectors were 512 bytes, we now made the block size 2*512 or 1024). The code even has "sectors -> kbytes". So unless there is something very strange going on, pgpgin and pgpgout in /proc/vmstat return kibibytes. What about pages (which is sort of implied in the name) or blocks (as described on the man page)? Pages can vary, but they are generally 4 KiB so they're out. That also means vmstat -s lies :( Blocks are harder to discount. While these too can vary, they can be 1 KiB; they could also be something else (e.g dd its 512, filesystems 4096). However, for memory management inside the kernel, there are sectors and there are (near userland export) KiB, nothing else. It's probably more accurate to say sectors are shifted in and out of block devices and the kernel expresses these transfers to userland as KiB by halving the numbers. What all this means is that using KiB for bi/bo aka pgpgin/pgpgout is more accurate than saying blocks or pages. Signed-off-by: Craig Small <csmall@dropbear.xyz> References: procps-ng/procps!64 |
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|---|---|---|
| contrib | ||
| doc | ||
| Documentation | ||
| include | ||
| lib | ||
| man-po | ||
| misc | ||
| po | ||
| proc | ||
| ps | ||
| testsuite | ||
| top | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| AUTHORS | ||
| autogen.sh | ||
| ChangeLog | ||
| configure.ac | ||
| COPYING | ||
| COPYING.LIB | ||
| create-man-pot.sh | ||
| free.1 | ||
| free.c | ||
| INSTALL.md | ||
| kill.1 | ||
| kill.c | ||
| Makefile.am | ||
| NEWS | ||
| pgrep.1 | ||
| pgrep.c | ||
| pidof.1 | ||
| pidof.c | ||
| pidwait.1 | ||
| pkill.1 | ||
| pmap.1 | ||
| pmap.c | ||
| pwdx.1 | ||
| pwdx.c | ||
| README.md | ||
| skill.1 | ||
| skill.c | ||
| slabtop.1 | ||
| slabtop.c | ||
| snice.1 | ||
| sysctl.8 | ||
| sysctl.c | ||
| sysctl.conf | ||
| sysctl.conf.5 | ||
| tload.1 | ||
| tload.c | ||
| translate-man.sh | ||
| uptime.1 | ||
| uptime.c | ||
| vmstat.8 | ||
| vmstat.c | ||
| w.1 | ||
| w.c | ||
| watch.1 | ||
| watch.c | ||
procps
procps is a set of command line and full-screen utilities that provide information out of the pseudo-filesystem most commonly located at /proc. This filesystem provides a simple interface to the kernel data structures. The programs of procps generally concentrate on the structures that describe the processess running on the system.
The following programs are found in procps:
- free - Report the amount of free and used memory in the system
- kill - Send a signal to a process based on PID
- pgrep - List processes based on name or other attributes
- pkill - Send a signal to a process based on name or other attributes
- pmap - Report memory map of a process
- ps - Report information of processes
- pwdx - Report current directory of a process
- skill - Obsolete version of pgrep/pkill
- slabtop - Display kernel slab cache information in real time
- snice - Renice a process
- sysctl - Read or Write kernel parameters at run-time
- tload - Graphical representation of system load average
- top - Dynamic real-time view of running processes
- uptime - Display how long the system has been running
- vmstat - Report virtual memory statistics
- w - Report logged in users and what they are doing
- watch - Execute a program periodically, showing output fullscreen
Reporting Bugs
There are a few ways of reporting bugs or feature requests:
- Your distribution's bug reporter. If you are using a distribution your first port of call is their bug tracker. This is because each distribution has their own patches and way of dealing with bugs. Also bug reporting often does not need any subscription to websites.
- GitLab Issues - To the left of this page is the issue tracker. You can report bugs here.
- Email list - We have an email list (see below) where you can report bugs. The problem with this method is bug reports often get lost and cannot be tracked. This is especially a big problem when its something that will take time to resolve.
If you need to report bugs, there is more details on the Bug Reporting page.
Email List
The email list for the developers and users of procps is found at http://www.freelists.org/archive/procps/ This email list discusses the development of procps and is used by distributions to also forward or discuss bugs.