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| author | Matthew Ahrens <[email protected]> | 2020-06-26 18:05:28 -0700 |
|---|---|---|
| committer | GitHub <[email protected]> | 2020-06-26 18:05:28 -0700 |
| commit | 7b232e93548a187beb5490314dad181f9ce6b17c (patch) | |
| tree | 8776bbb46c8d5200144c6ba77163fa18e79fb4be /man | |
| parent | bfcbec6f5d8aad60365eaeacff21df92c04c26df (diff) | |
arcstat: add 'avail', fix 'free'
The meaning of the `free` field is currently `zfs_arc_sys_free`, which
is the target amount of memory to leave free for the system, and is
constant after booting.
This commit changes the meaning of `free` to arc_free_memory(), the
amount of memory that the ARC considers to be free.
It also adds a new arcstat field `avail`, which tracks
`arc_available_memory()`.
Since `avail` can be negative, it also updates the arcstat script to
pretty-print negative values.
example output:
$ arcstat -f time,miss,arcsz,c,grow,need,free,avail 1
time miss arcsz c grow need free avail
15:03:02 39K 114G 114G 0 0 2.4G 407M
15:03:03 42K 114G 114G 0 0 2.1G 120M
15:03:04 40K 114G 114G 0 0 1.8G -177M
15:03:05 24K 113G 112G 0 0 1.7G -269M
15:03:06 29K 111G 110G 0 0 1.6G -385M
15:03:07 27K 110G 108G 0 0 1.4G -535M
15:03:08 13K 108G 108G 0 0 2.2G 239M
15:03:09 33K 107G 107G 0 0 1.3G -639M
15:03:10 16K 105G 102G 0 0 2.6G 704M
15:03:11 7.2K 102G 102G 0 0 5.1G 3.1G
15:03:12 42K 103G 102G 0 0 4.8G 2.8G
Reviewed-by: George Melikov <[email protected]>
Reviewed-by: Pavel Zakharov <[email protected]>
Reviewed-by: Tony Nguyen <[email protected]>
Signed-off-by: Matthew Ahrens <[email protected]>
Closes #10494
Diffstat (limited to 'man')
| -rw-r--r-- | man/man1/arcstat.1 | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/man/man1/arcstat.1 b/man/man1/arcstat.1 index 6dcc39b67..9113b76af 100644 --- a/man/man1/arcstat.1 +++ b/man/man1/arcstat.1 @@ -236,7 +236,7 @@ Time .sp .ne 2 .na -\fBarcsz \fR +\fBsize \fR .ad .RS 14n ARC size @@ -245,6 +245,15 @@ ARC size .sp .ne 2 .na +\fBarcsz \fR +.ad +.RS 14n +Alias for \fBsize\fR +.RE + +.sp +.ne 2 +.na \fBdread \fR .ad .RS 14n @@ -392,7 +401,18 @@ ARC reclaim needed \fBfree \fR .ad .RS 14n -ARC free memory +The ARC's idea of how much free memory there is, which includes evictable memory in the page cache. +Since the ARC tries to keep \fBavail\fR above zero, \fBavail\fR is usually more instructive to observe than \fBfree\fR. +.RE + +.sp +.ne 2 +.na +\fBavail \fR +.ad +.RS 14n +The ARC's idea of how much free memory is available to it, which is a bit less than \fBfree\fR. +May temporarily be negative, in which case the ARC will reduce the target size \fBc\fR. .RE .\" |