Re: [PATCH] qemu: add unmap stats to all domain stats
On Thu, Jun 01, 2023 at 12:44:19 +0600, Oleg Vasilev wrote:
From: Nikolay Shirokovskiy <nshirokovskiy(a)virtuozzo.com>
Unmap stats are useful for debugging how efficient qemu is in freeing host
disk space.
"debugging [..] qemu" seems a bit too weak of a justification. Do you
have any better usage for this data?
Signed-off-by: Oleg Vasilev <oleg.vasilev(a)virtuozzo.com>
Missing sign-off by original author. (See 'From' field above)
---
src/qemu/qemu_driver.c | 3 +++
src/qemu/qemu_monitor.h | 3 +++
src/qemu/qemu_monitor_json.c | 3 +++
3 files changed, 9 insertions(+)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 5ee15bab7a..6725bddff9 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -17451,6 +17451,9 @@ qemuDomainGetStatsBlockExportFrontend(const char *frontendname,
virTypedParamListAddULLong(par, en->wr_req, "block.%zu.wr.reqs",
idx) < 0 ||
virTypedParamListAddULLong(par, en->wr_bytes, "block.%zu.wr.bytes",
idx) < 0 ||
virTypedParamListAddULLong(par, en->wr_total_times,
"block.%zu.wr.times", idx) < 0 ||
+ virTypedParamListAddULLong(par, en->unmap_req, "block.%zu.un.reqs",
idx) < 0 ||
+ virTypedParamListAddULLong(par, en->unmap_bytes,
"block.%zu.un.bytes", idx) < 0 ||
+ virTypedParamListAddULLong(par, en->unmap_total_times,
"block.%zu.un.times", idx) < 0 ||
Missing documentation for the new fields in:
docs/manpages/virsh.rst - section for 'domstats' has:
* ``block.<num>.rd.times`` - total time (ns) spent on reads
* ``block.<num>.wr.reqs`` - number of write requests
* ``block.<num>.wr.bytes`` - number of written bytes
* ``block.<num>.wr.times`` - total time (ns) spent on writes
src/libvirt-domain.c - function comment for 'virConnectGetAllDomainStats'
* "block.<num>.wr.reqs" - number of write requests as unsigned long
long.
* "block.<num>.wr.bytes" - number of written bytes as unsigned long
long.
* "block.<num>.wr.times" - total time (ns) spent on writes as
* unsigned long long.
also, both internally and in qemu it's spelled 'unmap' so consider
spelling it in full here too.
Good thing is that the stats are reported since qemu-4.2 which is the
minimum supported version so you don't need to add any special handling
for the case if it weren't present.