system/freebsd-src
system/freebsd-src
1
0
Fork 0
mirror of https://github.com/freebsd/freebsd-src synced 2024-07-22 10:48:02 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

geom: Add counts for enomem and pausing

Browse source 
Add counts for the number of requests that complete with the ENOMEM as
kern.geom.nomem_count and the number of times we pause the g_down thread
to let the system recover as kern.geom.pause_count.

Sponsored by:		Netflix
Reviewed by:		kib
Differential Revision:	https://reviews.freebsd.org/D45309
This commit is contained in:
Warner Losh 2024-05-24 08:31:15 -06:00
parent 1d3c23676d
commit 32f40fc983
1 changed files with 11 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
sys/geom/geom_io.c
View file

@ -75,6 +75,9 @@ static int g_io_transient_map_bio(struct bio *bp);
static struct g_bioq g_bio_run_down;
static struct g_bioq g_bio_run_up;
static u_long nomem_count;
static u_long pause_count;
/*
* Pace is a hint that we've had some trouble recently allocating
* bios, so we should back off trying to send I/O down the stack
@ -701,6 +704,7 @@ g_io_deliver(struct bio *bp, int error)
if (bootverbose)
printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
atomic_add_long(&nomem_count, 1); /* Rare event, but no locks held */
bp->bio_children = 0;
bp->bio_inbed = 0;
bp->bio_driver1 = NULL;
@ -734,6 +738,12 @@ int inflight_transient_maps;
SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD,
&inflight_transient_maps, 0,
"Current count of the active transient maps");
SYSCTL_ULONG(_kern_geom, OID_AUTO, nomem_count, CTLFLAG_RD,
&nomem_count, 0,
"Total count of requests completed with status of ENOMEM");
SYSCTL_ULONG(_kern_geom, OID_AUTO, pause_count, CTLFLAG_RD,
&pause_count, 0,
"Total count of requests stalled due to low memory in g_down");
static int
g_io_transient_map_bio(struct bio *bp)
@ -822,6 +832,7 @@ g_io_schedule_down(struct thread *tp __unused)
* for that I/O.
*/
CTR0(KTR_GEOM, "g_down pacing self");
pause_count++; /* g_down has only one thread */
pause("g_down", min(hz/1000, 1));
pace = 0;
}