Every time we call all domain stats for inactive domain with unavailable storage source we get error message in logs [1]. It's a bit noisy. While it's arguable whether we need such message or not for mandatory disks we would like not to see messages for optional disks. Let's filter at least for cases of local files. Fixing other cases would require passing flag down the stack to .backendInit of storage which is ugly. Stats for active domain are fine because we either drop disks with unavailable sources or clean source which is handled by virStorageSourceIsEmpty in qemuDomainGetStatsOneBlockFallback. We have these logs for successful stats since 25aa7035d (version 1.2.15) which in turn fixes 596a13713 (version 1.2.12 )which added substantial stats for offline disks. [1] error message example: qemuOpenFileAs:3324 : Failed to open file '/path/to/optional/disk': No such file or directory Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy(a)virtuozzo.com&gt; --- src/qemu/qemu_domain.c | 9 +++++++++ src/qemu/qemu_domain.h | 3 +++ src/qemu/qemu_driver.c | 14 ++++++++++++++ 3 files changed, 26 insertions(+) diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 1eb0e31..6f8df23 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -13696,3 +13696,12 @@ qemuDomainIsUsingNoShutdown(qemuDomainObjPrivatePtr priv) { return priv->monJSON && priv->allowReboot == VIR_TRISTATE_BOOL_YES; } + + +bool +qemuDomainDiskIsMissingLocalOptional(virDomainDiskDefPtr disk) +{ + return disk->startupPolicy == VIR_DOMAIN_STARTUP_POLICY_OPTIONAL && + virStorageSourceIsLocalStorage(disk->src) && disk->src->path && + !virFileExists(disk->src->path); +} diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h index 53b5ea1..b57fa19 100644 --- a/src/qemu/qemu_domain.h +++ b/src/qemu/qemu_domain.h @@ -1094,4 +1094,7 @@ qemuDomainRunningReasonToResumeEvent(virDomainRunningReason reason); bool qemuDomainIsUsingNoShutdown(qemuDomainObjPrivatePtr priv); +bool +qemuDomainDiskIsMissingLocalOptional(virDomainDiskDefPtr disk); + #endif /* __QEMU_DOMAIN_H__ */ diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index d0cf2c1..c2f3b74 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -20722,6 +20722,20 @@ qemuDomainGetStatsBlockExportDisk(virDomainDiskDefPtr disk, const char *backendstoragealias; int ret = -1; + /* + * This helps to keep logs clean from error messages on getting stats + * for optional disk with nonexistent source file. We won't get any + * stats for such a disk anyway in below code. + */ + if (!virDomainObjIsActive(dom) && + qemuDomainDiskIsMissingLocalOptional(disk)) { + VIR_INFO("optional disk '%s' source file is missing, " + "skip getting stats", disk->dst); + + return qemuDomainGetStatsBlockExportHeader(disk, disk->src, *recordnr, + records, nrecords); + } + for (n = disk->src; virStorageSourceIsBacking(n); n = n->backingStore) { if (blockdev) { frontendalias = QEMU_DOMAIN_DISK_PRIVATE(disk)->qomName; -- 1.8.3.1

Because missing optional storage source is not error. The patch address only local files. Fixing other cases is a bit ugly. Below is example of error notice in log now: error: virStorageFileReportBrokenChain:427 : Cannot access storage file '/path/to/missing/optional/disk': No such file or directory Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy(a)virtuozzo.com&gt; --- src/qemu/qemu_process.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index 2f8e19d..d754f09 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -6118,7 +6118,15 @@ qemuProcessPrepareHostStorage(virQEMUDriverPtr driver, if (!blockdev) virStorageSourceBackingStoreClear(disk->src); - if (qemuDomainDetermineDiskChain(driver, vm, disk, true) >= 0) + /* + * Go to applying startup policy for optional disk with nonexistent + * source file immediately as detemining chain will surely fail + * and we don't want noisy error notice in logs for this case. + */ + if (qemuDomainDiskIsMissingLocalOptional(disk) && cold_boot) + VIR_INFO("optional disk '%s' source file is missing, " + "skip checking disk chain", disk->dst); + else if (qemuDomainDetermineDiskChain(driver, vm, disk, true) >= 0) continue; if (qemuDomainCheckDiskStartupPolicy(driver, vm, idx, cold_boot) >= 0) -- 1.8.3.1