search for: dbuf_sync

...zfs`space_map_alloc+0x10 zfs`metaslab_group_alloc+0x1e0 zfs`metaslab_alloc_dva+0x114 zfs`metaslab_alloc+0x2c zfs`zio_dva_allocate+0x4c zfs`zio_write_compress+0x1ec zfs`arc_write+0xe4 zfs`dbuf_sync+0x6c0 zfs`dnode_sync+0x35c zfs`dmu_objset_sync_dnodes+0x6c zfs`dmu_objset_sync+0x54 zfs`dsl_dataset_sync+0xc zfs`dsl_pool_sync+0x64 zfs`spa_sync+0x1b0 zfs`txg_sync_thread+0x134 unix`threa...

Hi. System is snv_56 sun4u sparc SUNW,Sun-Fire-V440, zil_disable=1 We see many operation on nfs clients to that server really slow (like 90 seconds for unlink()). It''s not a problem with network, there''s also plenty oc CPU available. Storage isn''t saturated either. First strange thing - normally on that server nfsd has about 1500-2500 number of threads. I did

...zfs`metaslab_activate+0x3c zfs`metaslab_group_alloc+0x1b0 zfs`metaslab_alloc_dva+0x10c zfs`metaslab_alloc+0x2c zfs`zio_dva_allocate+0x50 zfs`zio_write_compress+0x1e4 zfs`arc_write+0xbc zfs`dbuf_sync+0x6b0 zfs`dnode_sync+0x300 zfs`dmu_objset_sync_dnodes+0x68 zfs`dmu_objset_sync+0x50 zfs`dsl_dataset_sync+0xc zfs`dsl_pool_sync+0x60 zfs`spa_sync+0xe0 zfs`txg_sync_thread+0x130 unix`thread...

We are using MySQL, and love the idea of using zfs for this. We are used to using Direct I/O to bypass file system caching (let the DB do this). Does this exist for zfs? This message posted from opensolaris.org

...fs:zio_next_stage+66 (e3c0a580) d2c8aadc zfs:zio_wait_for_children+46 (e3c0a580, 1, e3c0a7) d2c8aaf0 zfs:zio_wait_children_ready+18 (e3c0a580) d2c8ab04 zfs:zio_next_stage_async+ac (e3c0a580, 0, f8dbfe) d2c8ab1c zfs:zio_nowait+e (e3c0a580) d2c8ab3c zfs:arc_write+7b (e44c9780, d895e8c0,) d2c8abec zfs:dbuf_sync+5f3 (dbd6ef00, e44c9780,) d2c8ac4c zfs:dnode_sync+33a (d34fbb30, 1, e44c97) d2c8ac80 zfs:dmu_objset_sync_dnodes+7e (d2380240, d23802fc,) d2c8acd0 zfs:dmu_objset_sync+5d (d2380240, e96f1e80) d2c8ad1c zfs:dsl_pool_sync+121 (d244a180, 15e234, 0) d2c8ad6c zfs:spa_sync+10a (d895e8c0, 15e234, 0) d2c8adc8...