On Thu, 12 May 2011, Fyodor Ustinov wrote: > Hi! > > Like previous, but ceph fs instead of rbd. > (i.e. iozone with 4G file). > > [ 783.295035] ceph: loaded (mds proto 32) > [ 783.300122] libceph: client4125 fsid ff352dfd-078c-e65f-a769-d25abb384d92 > [ 783.300642] libceph: mon0 77.120.112.193:6789 session established > [ 941.278185] libceph: msg_new can't create type 0 front 4096 > [ 941.278456] libceph: msgpool osd_op alloc failed > [ 941.278539] libceph: msg_new can't create type 0 front 512 > [ 941.278606] libceph: msgpool osd_op_reply alloc failed > [ 941.278670] libceph: msg_new can't create type 0 front 4096 > [ 941.278737] libceph: msgpool osd_op alloc failed > [ 941.278808] libceph: msg_new can't create type 0 front 512 > [ 941.278875] libceph: msgpool osd_op_reply alloc failed > [ 941.279011] libceph: msg_new can't create type 0 front 4096 > [ 941.279079] libceph: msgpool osd_op alloc failed > [ 941.279153] libceph: msg_new can't create type 0 front 512 > [ 941.279220] libceph: msgpool osd_op_reply alloc failed > [ 941.279286] libceph: msg_new can't create type 0 front 4096 > [ 941.279352] libceph: msgpool osd_op alloc failed > [ 941.279422] libceph: msg_new can't create type 0 front 512 > [ 941.279623] libceph: msgpool osd_op_reply alloc failed > [ 941.279692] libceph: msg_new can't create type 0 front 4096 > [ 941.279897] libceph: msgpool osd_op alloc failed > [ 941.280042] libceph: msg_new can't create type 0 front 512 > [ 941.280300] libceph: msgpool osd_op_reply alloc failed > [ 941.280418] libceph: msg_new can't create type 0 front 4096 > [ 941.280534] libceph: msgpool osd_op alloc failed > [ 941.280793] libceph: msg_new can't create type 0 front 512 > [ 941.280958] libceph: msgpool osd_op_reply alloc failed > [ 941.281074] libceph: msg_new can't create type 0 front 4096 > [ 941.281236] libceph: msgpool osd_op alloc failed The ceph memory allocations are definitely not bulletproof and low memory situations can still cause problems. I'm not sure that that is what is going on here, but you might try adjusting vm.min_free_kbytes and see if that has an effect. e.g., sysctl -w vm.min_free_kbytes=262144 (although I'd check the current value first to make sure you're adjusting it up). sage -- 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