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  1. Lustre
  2. LU-7235

ZFS: dmu_object_alloc() serializes object creations

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    • Resolution: Fixed
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      dmu_object_alloc() in ZFS serializes object creations with a mutex:

      dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
                  int dmu_object_type_t bonustype,
                  int bonuslen, dmu_tx_t *tx)
{
	uint64_t object;
	uint64_t L2_dnode_count = DNODES_PER_BLOCK <<
	    (DMU_META_DNODE(os)->dn_indblkshift - SPA_BLKPTRSHIFT);
	dnode_t *dn = NULL;
	int restarted = B_FALSE;

	mutex_enter(&os->os_obj_lock);

      this can be a bottleneck holding metadata performance much lower compared to ldiskfs where inode creation is more concurrent.

        1. dmu_object_alloc-call-graph.txt
          121 kB

            bzzz Alex Zhuravlev
            bzzz Alex Zhuravlev
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              Created:
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