hi, We create one million empty files through filebench, here is the test env: MDS: one MDS MON: one MON OSD: two OSD, each with one Inter P3700; data on OSD with 2x replica Network: all nodes are connected through 10 gigabit network
We use more than one client to create files, to test the scalability of MDS. Here are the results: IOPS under one client: 850 IOPS under two client: 1150 IOPS under four client: 1180 As we can see, the IOPS almost maintains unchanged when the number of client increase from 2 to 4. Cephfs may have a low scalability under one MDS, and we think its the big lock in MDSDamon::ms_dispatch()::Mutex::locker(every request acquires this lock), who limits the scalability of MDS. We think this big lock could be removed through the following steps: 1. separate the process of ClientRequest with other requests, so we can parallel the process of ClientRequest 2. use some small granularity locks instead of big lock to ensure consistency Wondering this idea is reasonable? thanks -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
