Introduce an I/O semaphore to limit the number of concurrent
disk-IO-intensive operations. This could reduce disk contention from
image operations like image download, image format conversion, snapshot
extraction, etc.
The new config option max_concurrent_disk_ops can be set in nova.conf
per compute host and would be virt-driver-agnostic. It is default to 0
which means no limit.
blueprint: io-semaphore-for-concurrent-disk-ops
Change-Id: I897999e8a4601694213f068367eae9608cdc7bbb
Signed-off-by: Jack Ding <jack.ding@windriver.com>
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