Mercurial > dovecot > original-hg > dovecot-1.2

changeset 1016:d1caf5d0e77c HEAD

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Modify log used to test if there were other users for every changed flag or expunged message, causing two fcntl() syscalls every time -> SLOW. Now we check it only once after exclusively locking the index.
author Timo Sirainen <tss@iki.fi>
date Wed, 22 Jan 2003 21:52:17 +0200
parents 40a327d356de
children a237bde6bd1e
files src/lib-index/mail-index.c src/lib-index/mail-index.h src/lib-index/mail-modifylog.c
diffstat 3 files changed, 26 insertions(+), 2 deletions(-) [+]
line wrap: on
line diff
--- a/src/lib-index/mail-index.c	Wed Jan 22 21:23:28 2003 +0200
+++ b/src/lib-index/mail-index.c	Wed Jan 22 21:52:17 2003 +0200
@@ -391,6 +391,7 @@
 		/* while holding exclusive lock, keep the FSCK flag on.
 		   when the lock is released, the FSCK flag will also be
 		   removed. */
+		index->excl_lock_counter++;
 		index->header->flags |= MAIL_INDEX_FLAG_FSCK;
 		if (!mail_index_fmdatasync(index,
 					   sizeof(struct mail_index_header))) {
@@ -421,6 +422,7 @@
 	}
 
 	if (index->lock_type == MAIL_LOCK_EXCLUSIVE) {
+		index->excl_lock_counter++;
 		if (index->modifylog != NULL)
 			mail_modifylog_notify_lock_drop(index->modifylog);
 
--- a/src/lib-index/mail-index.h	Wed Jan 22 21:23:28 2003 +0200
+++ b/src/lib-index/mail-index.h	Wed Jan 22 21:52:17 2003 +0200
@@ -362,6 +362,9 @@
 	unsigned int indexid;
 	unsigned int sync_id;
 
+        /* updated whenever exclusive lock is set/unset */
+	unsigned int excl_lock_counter;
+
 	int mbox_fd;
 	struct istream *mbox_stream;
 	enum mail_lock_type mbox_lock_type;
@@ -421,7 +424,7 @@
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
-	0
+	0, 0
 #endif
 
 /* defaults - same as above but prefixed with mail_index_. */
--- a/src/lib-index/mail-modifylog.c	Wed Jan 22 21:23:28 2003 +0200
+++ b/src/lib-index/mail-modifylog.c	Wed Jan 22 21:52:17 2003 +0200
@@ -60,6 +60,9 @@
 
 	struct modify_log_file file1, file2;
 	struct modify_log_file *head, *tail;
+
+	int cache_have_others;
+	unsigned int cache_lock_counter;
 };
 
 static const struct modify_log_expunge no_expunges = { 0, 0, 0 };
@@ -707,18 +710,34 @@
 	i_assert((*rec)->seq1 != 0);
 	i_assert((*rec)->uid1 != 0);
 
-	if (!external_change) {
+	if (!external_change &&
+	    file->log->cache_lock_counter !=
+	    file->log->index->excl_lock_counter) {
 		switch (modifylog_have_other_users(file->log, FALSE)) {
 		case 0:
 			/* we're the only one having this log open,
 			   no need for modify log. */
+			file->log->cache_have_others = FALSE;
+			file->log->cache_lock_counter =
+				file->log->index->excl_lock_counter;
+
 			*rec = NULL;
 			return TRUE;
 		case -1:
 			return FALSE;
+		default:
+			file->log->cache_have_others = TRUE;
+			file->log->cache_lock_counter =
+				file->log->index->excl_lock_counter;
+			break;
 		}
 	}
 
+	if (!file->log->cache_have_others) {
+		*rec = NULL;
+		return FALSE;
+	}
+
 	if (file->mmap_used_length == file->mmap_full_length) {
 		if (!mail_modifylog_grow(file))
 			return FALSE;