i found a discuss on two years ago (http://permalink.gmane.org/gmane.comp.file-systems.ceph.devel/23872) and a pr commited by XinzeChi(https://github.com/ceph/ceph/pull/4467)... 2017-11-09 19:10 GMT+08:00 zengran zhang <z13121369189@xxxxxxxxx>: > Hi all: > we found that partial read will cause full stripe read in now ec > impl, for example: > we have 4 chunks per stripe, 4K size per chunks and 16K per > stripe, when we read rand 2K in a stripe,the reads > will amplify to full stripe(16K +8K(Parity)).. > > i did not see any checksum or buffer related factor except the ec > extentcache.does the extentcache is the purpuse of the mechanism? > now we want increase the stripe width to improve the small random raed > performance, but the mechanism limit the result... > > best regards! -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
