NAME
vm_stat – show Mach virtual memory statistics
SYNOPSIS
vm_stat[ [-c count] interval]
DESCRIPTION
vm_stat displays Mach virtual memory statistics. If the optional interval is specified, then vm_stat will display the statistics every interval seconds. In this case, each line of output displays the change in each statistic (an interval count of 1 displays the values per second). However, the first line of output following each banner displays the system-wide totals for each statistic. If a count is provided, the command will terminate after count intervals. The following values are displayed:
- Pages free
-
the total number of free pages in the system.
- Pages active
-
the total number of pages currently in use and pageable.
- Pages inactive
-
the total number of pages on the inactive list.
- Pages speculative
-
the total number of pages on the speculative list.
- Pages throttled
-
the total number of pages on the throttled list (not wired but not pageable).
- Pages wired down
-
the total number of pages wired down. That is, pages that cannot be paged out.
- Pages purgeable
-
the total number of purgeable pages.
- Translation faults
-
the number of times the "vm_fault" routine has been called.
- Pages copy-on-write
-
the number of faults that caused a page to be copied (generally caused by copy-on-write faults).
- Pages zero filled
-
the total number of pages that have been zero-filled on demand.
- Pages reactivated
-
the total number of pages that have been moved from the inactive list to the active list (reactivated).
- Pages purged
-
the total number of pages that have been purged.
- File-backed pages
-
the total number of pages that are file-backed (non-swap)
- Anonymous pages
-
the total number of pages that are anonymous
- Uncompressed pages
-
the total number of pages (uncompressed) held within the compressor
- Pages used by VM compressor:
-
the number of pages used to store compressed VM pages.
- Pages decompressed
-
the total number of pages that have been decompressed by the VM compressor.
- Pages compressed
-
the total number of pages that have been compressed by the VM compressor.
- Pageins
-
the total number of requests for pages from a pager (such as the inode pager).
- Pageouts
-
the total number of pages that have been paged out.
- Swapins
-
the total number of compressed pages that have been swapped back in from disk.
- Swapouts
-
the total number of compressed pages that have been swapped out to disk.
If the system supports the ARM Memory Tagging Extension (MTE), then the following values will additionally be displayed:
- Pages tagged
-
the total number of virtual pages which have been assigned memory tags.
- Pages tagged resident
-
the number of tagged pages which are resident in memory.
- Pages tagged compressed
-
the number of tagged pages which have been evicted to the compressor.
- Pages tag storage
-
the total number of physical pages which may be used to store memory tags.
- Pages tag storage holding tags
-
the number of physical pages which are currently being used to store memory tags.
- Pages tag storage free
-
the number of tag-storage pages which are unused.
- Pages tag storage non-tag pageable
-
the number of tag-storage pages which are being used to store pageable non-tag data.
- Pages tag storage non-tag wired
-
the number of tag-storage pages which are being used to store wired non-tag data.
- Bytes of compressed tags
-
the (post-compression) size of memory tags currently held in the compressor in bytes.
- Tagged compressions
-
the number of tagged pages which have been compressed.
- Tagged decompressions
-
the number of tagged pages which have been decompressed.
If interval is not specified, then vm_stat displays all accumulated statistics along with the page size.