Commit f1985535 authored by Ben Walker's avatar Ben Walker Committed by Jim Harris
Browse files

blob: Coalesce unmaps 



Previously, each freed cluster was unmapped individually.
Instead, coalesce unmaps for contiguous clusters to reduce
the volume of commands sent.

Change-Id: I6ea1d2e1235e3c030cd2826c97e57aca571bd2ae
Signed-off-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-on: https://review.gerrithub.io/362773


Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
parent 7058f853

lib/blob/blobstore.c

+28 −2
Original line number Diff line number Diff line
@@ -673,6 +673,8 @@ _spdk_blob_persist_unmap_clusters(spdk_bs_sequence_t *seq, void *cb_arg, int bse 
	struct spdk_blob_store		*bs = blob->bs;

	spdk_bs_batch_t			*batch;

	size_t				i;

	uint64_t			lba;

	uint32_t			lba_count;



	/* Clusters don't move around in blobs. The list shrinks or grows

	 * at the end, but no changes ever occur in the middle of the list.
@@ -681,10 +683,34 @@ _spdk_blob_persist_unmap_clusters(spdk_bs_sequence_t *seq, void *cb_arg, int bse 
	batch = spdk_bs_sequence_to_batch(seq, _spdk_blob_persist_unmap_clusters_cpl, ctx);



	/* Unmap all clusters that were truncated */

	lba = 0;

	lba_count = 0;

	for (i = blob->active.num_clusters; i < blob->active.cluster_array_size; i++) {

		uint64_t lba = blob->active.clusters[i];

		uint32_t lba_count = _spdk_bs_cluster_to_lba(bs, 1);

		uint64_t next_lba = blob->active.clusters[i];

		uint32_t next_lba_count = _spdk_bs_cluster_to_lba(bs, 1);



		if ((lba + lba_count) == next_lba) {

			/* This cluster is contiguous with the previous one. */

			lba_count += next_lba_count;

			continue;

		}



		/* This cluster is not contiguous with the previous one. */



		/* If a run of LBAs previously existing, send them

		 * as an unmap.

		 */

		if (lba_count > 0) {

			spdk_bs_batch_unmap(batch, lba, lba_count);

		}



		/* Start building the next batch */

		lba = next_lba;

		lba_count = next_lba_count;

	}



	/* If we ended with a contiguous set of LBAs, send the unmap now */

	if (lba_count > 0) {

		spdk_bs_batch_unmap(batch, lba, lba_count);

	}