Author: mav
Date: Fri Nov 13 09:18:33 2015
New Revision: 290750
URL: https://svnweb.freebsd.org/changeset/base/290750
Log:
MFC r289297: 6288 dmu_buf_will_dirty could be faster
Reviewed by: George Wilson <george.wil...@delphix.com>
Reviewed by: Paul Dagnelie <p...@delphix.com>
Reviewed by: Justin Gibbs <gi...@scsiguy.com>
Reviewed by: Richard Elling <richard.ell...@richardelling.com>
Approved by: Robert Mustacchi <r...@joyent.com>
Author: Matthew Ahrens <mahr...@delphix.com>
illumos/illumos-gate@0f2e7d03b8f588387cb8dd8dd500cbe5ff4484e0
Modified:
stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c
Directory Properties:
stable/10/ (props changed)
Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c
==============================================================================
--- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c Fri Nov
13 09:17:48 2015 (r290749)
+++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c Fri Nov
13 09:18:33 2015 (r290750)
@@ -1110,6 +1110,32 @@ dbuf_release_bp(dmu_buf_impl_t *db)
(void) arc_release(db->db_buf, db);
}
+/*
+ * We already have a dirty record for this TXG, and we are being
+ * dirtied again.
+ */
+static void
+dbuf_redirty(dbuf_dirty_record_t *dr)
+{
+ dmu_buf_impl_t *db = dr->dr_dbuf;
+
+ ASSERT(MUTEX_HELD(&db->db_mtx));
+
+ if (db->db_level == 0 && db->db_blkid != DMU_BONUS_BLKID) {
+ /*
+ * If this buffer has already been written out,
+ * we now need to reset its state.
+ */
+ dbuf_unoverride(dr);
+ if (db->db.db_object != DMU_META_DNODE_OBJECT &&
+ db->db_state != DB_NOFILL) {
+ /* Already released on initial dirty, so just thaw. */
+ ASSERT(arc_released(db->db_buf));
+ arc_buf_thaw(db->db_buf);
+ }
+ }
+}
+
dbuf_dirty_record_t *
dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t *tx)
{
@@ -1182,16 +1208,7 @@ dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t
if (dr && dr->dr_txg == tx->tx_txg) {
DB_DNODE_EXIT(db);
- if (db->db_level == 0 && db->db_blkid != DMU_BONUS_BLKID) {
- /*
- * If this buffer has already been written out,
- * we now need to reset its state.
- */
- dbuf_unoverride(dr);
- if (db->db.db_object != DMU_META_DNODE_OBJECT &&
- db->db_state != DB_NOFILL)
- arc_buf_thaw(db->db_buf);
- }
+ dbuf_redirty(dr);
mutex_exit(&db->db_mtx);
return (dr);
}
@@ -1495,6 +1512,30 @@ dmu_buf_will_dirty(dmu_buf_t *db_fake, d
ASSERT(tx->tx_txg != 0);
ASSERT(!refcount_is_zero(&db->db_holds));
+ /*
+ * Quick check for dirtyness. For already dirty blocks, this
+ * reduces runtime of this function by >90%, and overall performance
+ * by 50% for some workloads (e.g. file deletion with indirect blocks
+ * cached).
+ */
+ mutex_enter(&db->db_mtx);
+ dbuf_dirty_record_t *dr;
+ for (dr = db->db_last_dirty;
+ dr != NULL && dr->dr_txg >= tx->tx_txg; dr = dr->dr_next) {
+ /*
+ * It's possible that it is already dirty but not cached,
+ * because there are some calls to dbuf_dirty() that don't
+ * go through dmu_buf_will_dirty().
+ */
+ if (dr->dr_txg == tx->tx_txg && db->db_state == DB_CACHED) {
+ /* This dbuf is already dirty and cached. */
+ dbuf_redirty(dr);
+ mutex_exit(&db->db_mtx);
+ return;
+ }
+ }
+ mutex_exit(&db->db_mtx);
+
DB_DNODE_ENTER(db);
if (RW_WRITE_HELD(&DB_DNODE(db)->dn_struct_rwlock))
rf |= DB_RF_HAVESTRUCT;
_______________________________________________
svn-src-stable-10@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-stable-10
To unsubscribe, send any mail to "svn-src-stable-10-unsubscr...@freebsd.org"
