thank you, you remind me that open_ino could cause the reply message from OSD, and if there are too much concurrent open_ino, that would make mqueue keep taken by the OSDReply messages. and since MDSBeacon message got the lowest priority ? which make MDSBeacon keep in the bottom of the mqueue. Regards, Dongdong. > 在 2018年3月29日，上午9:37，Yan, Zheng <ukernel@xxxxxxxxx> 写道： > > On Thu, Mar 29, 2018 at 9:09 AM, 陶冬冬 <tdd21151186@xxxxxxxxx> wrote: >> Patrick, we are using 32G memory for the mds. >> Zheng, calling mds->heartbeat_reset() could make the healthy check pass so >> that monitor won’t kick it out. >> more frustrating me is about the laggy issue, from the monitor log, i can >> actually see the MDSBeacon are sent without delay. >> but about 50 seconds later, mds start handling that MDSBeacon message. >> so i’m wondering would that possible the message stayed in the mqueue for >> that long time (if the previous message is MDSMap with rejoin state, ant >> that rejoin take long time) >> (meantime, i will do some more investigating about this issue) >> > > If it's really caused by long wait in mqueue. we should limit > concurrent open_ino > started by MDCache::process_imported_caps() > > >> 在 2018年3月29日，上午8:10，Yan, Zheng <ukernel@xxxxxxxxx> 写道： >> >> On Wed, Mar 28, 2018 at 11:14 PM, 陶冬冬 <tdd21151186@xxxxxxxxx> wrote: >> >> Hi Zheng & Patrick, >> >> we are using v12.2.2. >> Recently we’ve met an mds laggy issue (significantly, about 50 seconds) >> i’ve traced the monitor and mds log and found that the MMDSBeacon message >> was actually sent to mds 50 seconds ago. >> so, looks like monitor isn’t laggy , and more worse is that i also found >> that the mds’s health check is failed and eventually monitor >> just kicked out this mds and make it respawn. >> by the way, this happened at rejoin phase. >> >> Following is my analysis : >> The mds health check failure is because the mds tick thread could not get >> the mds_lock due to rejoin. (i found rejoin has many missing ino needed to >> fetch) >> and this leads the mqueue of the DispatchQueue consumed by Dispatcher got >> very slow, eventually make MMDSBeacon in mqueue got dispatched after a big >> delay. >> >> >> how about calling mds->heartbeat_reset() in the loop that fetch inodes >> >> >> >> i want to know if my analysis make sense to you ? if so, i’m wondering can >> we make MMDSBeacon fast dispatch. >> >> Regards, >> Dongdong >> >> -- 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
