diff options
Diffstat (limited to 'results/classifier/111/review/1338957')
| -rw-r--r-- | results/classifier/111/review/1338957 | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/results/classifier/111/review/1338957 b/results/classifier/111/review/1338957 new file mode 100644 index 00000000..feb9141e --- /dev/null +++ b/results/classifier/111/review/1338957 @@ -0,0 +1,47 @@ +semantic: 0.269 +other: 0.110 +device: 0.101 +performance: 0.079 +graphic: 0.071 +files: 0.061 +PID: 0.060 +socket: 0.043 +vnc: 0.041 +boot: 0.040 +debug: 0.038 +network: 0.034 +permissions: 0.030 +KVM: 0.022 +performance: 0.446 +debug: 0.174 +device: 0.089 +other: 0.069 +files: 0.059 +KVM: 0.033 +semantic: 0.028 +PID: 0.022 +network: 0.019 +socket: 0.017 +permissions: 0.013 +graphic: 0.012 +boot: 0.010 +vnc: 0.008 + +RFE: add an event to report block devices watermark + +Add an event to report if a block device usage exceeds a threshold. The threshold should be configurable with a monitor command. The event should report the affected block device. Additional useful information could be the offset of the highest sector , like in the query-blockstats output. + +Rationale for the RFE +Managing applications, like oVirt (http://www.ovirt.org), make extensive use of thin-provisioned disk images. +In order to let the guest run flawlessly and be not unnecessarily paused, oVirt sets a watermark and automatically resized the image once the watermark is reached or exceeded. + +In order to detect the mark crossing, the managing application has no choice than aggressively polling the QEMU monitor +using the query-blockstats command. This lead to unnecessary system load, and is made even worse under scale: scenarios +with hunderds of VM are becoming not unusual. + +patch posted on qemu-devel, reviewd, acked and merged into maintainer's branch: +https://github.com/stefanha/qemu/commit/f050ea639522e9dd7e501ef285a2a12709b8726a + +Upstream here: +https://git.qemu.org/?p=qemu.git;a=commitdiff;h=e2462113b2003085ad16f15e1 + |