From: Chongyun Wu <wu.chongyun@xxxxxxx>
Let san_path_err_recovery_time path unstable can be
detected and not reinstate it until this path keep up in
san_path_err_recovery_time. It will fix heavy IO delay
caused by parts of paths state shaky in multipath device.
Test and result:
Run up eth1 30s and down eth1 30s with 100 loops script to
make some paths shaky in each multipath devices.
Using below multipath.conf configure in defaults section:
san_path_err_recovery_time 30
san_path_err_threshold 2
san_path_err_forget_rate 6
After test, not found any IO delay logs except several logs in the very
beginning which before san_path_err filter shaky path works .
If without above config and this patch there will be lots of IO delay
in syslog and some paths state change from up to down again and again.
Signed-off-by: Chongyun Wu <wu.chongyun@xxxxxxx>
---
multipathd/main.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/multipathd/main.c b/multipathd/main.c
index 70172d71..34a57689 100644
--- a/multipathd/main.c
+++ b/multipathd/main.c
@@ -1896,6 +1896,18 @@ static int check_path_reinstate_state(struct path * pp) {
goto reinstate_path;
}
get_monotonic_time(&curr_time);
+
+ /* If path became failed again or continue failed, should reset
+ * path san_path_err_forget_rate and path dis_reinstate_time to
+ * start a new stable check.
+ */
+ if ((pp->state != PATH_UP) && (pp->state != PATH_GHOST) &&
+ (pp->state != PATH_DELAYED)) {
+ pp->san_path_err_forget_rate =
+ pp->mpp->san_path_err_forget_rate;
+ pp->dis_reinstate_time = curr_time.tv_sec;
+ }
+
if ((curr_time.tv_sec - pp->dis_reinstate_time ) > pp->mpp->san_path_err_recovery_time) {
condlog(2,"%s : reinstate the path after err recovery time", pp->dev);
goto reinstate_path;
@@ -2066,6 +2078,11 @@ check_path (struct vectors * vecs, struct path * pp, int ticks)
pathinfo(pp, conf, 0);
pthread_cleanup_pop(1);
return 1;
+ } else if ((newstate != PATH_UP && newstate != PATH_GHOST) &&
+ (pp->state == PATH_DELAYED)) {
+ /* If path state become failed again cancel path delay state */
+ pp->state = newstate;
+ return 1;
}
if (!pp->mpp) {
if (!strlen(pp->wwid) &&
--
2.23.0
--
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