Vhostmd uses the update_interval value to sleep() between the metrics updates.
But a long runtime of the metrics updates can result in a noticeable longer
time between the updates and a consumer might read 'old' data after waiting
update_interval seconds.
Fix the delay between updates, that
'runtime of metrics update' + 'sleep time' matches the update_interval value.
---
vhostmd/vhostmd.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/vhostmd/vhostmd.c b/vhostmd/vhostmd.c
index e6a1283..d581f25 100644
--- a/vhostmd/vhostmd.c
+++ b/vhostmd/vhostmd.c
@@ -968,6 +968,9 @@ static int vhostmd_run(int diskfd)
}
while (!down) {
+ time_t run_time,
+ start_time = time(NULL);
+
vu_buffer_add(buf, "<metrics>\n", -1);
if (metrics_host_get(buf))
vu_log(VHOSTMD_ERR, "Failed to collect host metrics "
@@ -986,7 +989,11 @@ static int vhostmd_run(int diskfd)
#endif
if (ids)
free(ids);
- sleep(update_period);
+
+ run_time = time(NULL) - start_time;
+ if (run_time < update_period)
+ sleep(update_period - run_time);
+
vu_buffer_erase(buf);
}
vu_buffer_delete(buf);
--
2.15.2 (Apple Git-101.1)
_______________________________________________
virt-tools-list mailing list
virt-tools-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/virt-tools-list
