Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756134AbZCQWvU (ORCPT ); Tue, 17 Mar 2009 18:51:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751855AbZCQWvF (ORCPT ); Tue, 17 Mar 2009 18:51:05 -0400 Received: from ns1.suse.de ([195.135.220.2]:36793 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751270AbZCQWvE (ORCPT ); Tue, 17 Mar 2009 18:51:04 -0400 From: Mark Fasheh To: linux-kernel@vger.kernel.org Cc: ocfs2-devel@oss.oracle.com, Joel Becker , Tao Ma , Mark Fasheh Subject: [PATCH 16/32] ocfs2: Optimize inode group allocation by recording last used group. Date: Tue, 17 Mar 2009 13:01:06 -0700 Message-Id: <1237320082-12921-17-git-send-email-mfasheh@suse.com> X-Mailer: git-send-email 1.5.6 In-Reply-To: <1237320082-12921-1-git-send-email-mfasheh@suse.com> References: <1237320082-12921-1-git-send-email-mfasheh@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5374 Lines: 165 From: Tao Ma In ocfs2, the block group search looks for the "emptiest" group to allocate from. So if the allocator has many equally(or almost equally) empty groups, new block group will tend to get spread out amongst them. So we add osb_inode_alloc_group in ocfs2_super to record the last used inode allocation group. For more details, please see http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy. I have done some basic test and the results are a ten times improvement on some cold-cache stat workloads. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh --- fs/ocfs2/ocfs2.h | 3 +++ fs/ocfs2/suballoc.c | 32 ++++++++++++++++++++++++++++---- 2 files changed, 31 insertions(+), 4 deletions(-) diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h index e1844d5..b65d19c 100644 --- a/fs/ocfs2/ocfs2.h +++ b/fs/ocfs2/ocfs2.h @@ -343,6 +343,9 @@ struct ocfs2_super unsigned int osb_dx_mask; u32 osb_dx_seed[4]; + + /* the group we used to allocate inodes. */ + u64 osb_inode_alloc_group; }; #define OCFS2_SB(sb) ((struct ocfs2_super *)(sb)->s_fs_info) diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index b7a065e..4c1399c 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -66,6 +66,7 @@ static int ocfs2_block_group_alloc(struct ocfs2_super *osb, struct inode *alloc_inode, struct buffer_head *bh, u64 max_block, + u64 *last_alloc_group, int flags); static int ocfs2_cluster_group_search(struct inode *inode, @@ -407,6 +408,7 @@ static int ocfs2_block_group_alloc(struct ocfs2_super *osb, struct inode *alloc_inode, struct buffer_head *bh, u64 max_block, + u64 *last_alloc_group, int flags) { int status, credits; @@ -444,6 +446,11 @@ static int ocfs2_block_group_alloc(struct ocfs2_super *osb, goto bail; } + if (last_alloc_group && *last_alloc_group != 0) { + mlog(0, "use old allocation group %llu for block group alloc\n", + (unsigned long long)*last_alloc_group); + ac->ac_last_group = *last_alloc_group; + } status = ocfs2_claim_clusters(osb, handle, ac, @@ -518,6 +525,11 @@ static int ocfs2_block_group_alloc(struct ocfs2_super *osb, alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode); status = 0; + + /* save the new last alloc group so that the caller can cache it. */ + if (last_alloc_group) + *last_alloc_group = ac->ac_last_group; + bail: if (handle) ocfs2_commit_trans(osb, handle); @@ -535,6 +547,7 @@ static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb, struct ocfs2_alloc_context *ac, int type, u32 slot, + u64 *last_alloc_group, int flags) { int status; @@ -600,7 +613,8 @@ static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb, } status = ocfs2_block_group_alloc(osb, alloc_inode, bh, - ac->ac_max_block, flags); + ac->ac_max_block, + last_alloc_group, flags); if (status < 0) { if (status != -ENOSPC) mlog_errno(status); @@ -644,7 +658,7 @@ int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb, status = ocfs2_reserve_suballoc_bits(osb, (*ac), EXTENT_ALLOC_SYSTEM_INODE, - slot, ALLOC_NEW_GROUP); + slot, NULL, ALLOC_NEW_GROUP); if (status < 0) { if (status != -ENOSPC) mlog_errno(status); @@ -690,7 +704,8 @@ static int ocfs2_steal_inode_from_other_nodes(struct ocfs2_super *osb, status = ocfs2_reserve_suballoc_bits(osb, ac, INODE_ALLOC_SYSTEM_INODE, - slot, NOT_ALLOC_NEW_GROUP); + slot, NULL, + NOT_ALLOC_NEW_GROUP); if (status >= 0) { ocfs2_set_inode_steal_slot(osb, slot); break; @@ -707,6 +722,7 @@ int ocfs2_reserve_new_inode(struct ocfs2_super *osb, { int status; s16 slot = ocfs2_get_inode_steal_slot(osb); + u64 alloc_group; *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL); if (!(*ac)) { @@ -742,14 +758,22 @@ int ocfs2_reserve_new_inode(struct ocfs2_super *osb, goto inode_steal; atomic_set(&osb->s_num_inodes_stolen, 0); + alloc_group = osb->osb_inode_alloc_group; status = ocfs2_reserve_suballoc_bits(osb, *ac, INODE_ALLOC_SYSTEM_INODE, osb->slot_num, + &alloc_group, ALLOC_NEW_GROUP | ALLOC_GROUPS_FROM_GLOBAL); if (status >= 0) { status = 0; + spin_lock(&osb->osb_lock); + osb->osb_inode_alloc_group = alloc_group; + spin_unlock(&osb->osb_lock); + mlog(0, "after reservation, new allocation group is " + "%llu\n", (unsigned long long)alloc_group); + /* * Some inodes must be freed by us, so try to allocate * from our own next time. @@ -796,7 +820,7 @@ int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb, status = ocfs2_reserve_suballoc_bits(osb, ac, GLOBAL_BITMAP_SYSTEM_INODE, - OCFS2_INVALID_SLOT, + OCFS2_INVALID_SLOT, NULL, ALLOC_NEW_GROUP); if (status < 0 && status != -ENOSPC) { mlog_errno(status); -- 1.5.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/