RHEL5 - dm-log-clustered: Optimization - bundle clear/mark requests

RHEL5 - dm-log-clustered: Optimization - bundle clear/mark requests

[Jonathan Brassow]

Gitweb:        http://git.fedorahosted.org/git/cluster.git?p=cluster.git;a=commitdiff;h=288ee1d7d73d6d4b08dc2ae0d0fb66f70d23f2fd
Commit:        288ee1d7d73d6d4b08dc2ae0d0fb66f70d23f2fd
Parent:        9bf373dbb03a185e49e36db5075d50352436b9c1
Author:        Jonathan Brassow <jbrassow@redhat.com>
AuthorDate:    Thu Aug 28 08:46:36 2008 -0500
Committer:     Jonathan Brassow <jbrassow@redhat.com>
CommitterDate: Thu Aug 28 08:47:57 2008 -0500

dm-log-clustered: Optimization - bundle clear/mark requests

The order and timing of the clear/mark region requests is not
important - as long as they are completed before the next
flush.  So, we can group requests - sending up to ~50 at a
time, reducing netlink and cluster traffic.
---
 cmirror-kernel/src/dm-clog.c |   72 ++++++++++++++++++++++++++++++++++++++---
 1 files changed, 66 insertions(+), 6 deletions(-)

diff --git a/cmirror-kernel/src/dm-clog.c b/cmirror-kernel/src/dm-clog.c
index 62ad414..fef062d 100644
--- a/cmirror-kernel/src/dm-clog.c
+++ b/cmirror-kernel/src/dm-clog.c
@@ -401,10 +401,12 @@ static int cluster_in_sync(struct dirty_log *log, region_t region, int can_block
  *
  * Returns: 0 on success, < 0 on failure
  */
+#define GROUP_SIZE 50
 static int cluster_flush(struct dirty_log *log)
 {
-	int r = 0;
+	int size, marks, clears, m, c, r = 0;
 	int flags;
+	region_t *m_ptr, *c_ptr;
 	struct log_c *lc = (struct log_c *)log->context;
 	LIST_HEAD(flush_list);
 	struct flush_entry *fe, *tmp_fe;
@@ -417,21 +419,74 @@ static int cluster_flush(struct dirty_log *log)
 		return 0;
 
 	/*
-	 * FIXME: Count up requests, group request types,
+	 * Count up requests, group request types,
 	 * allocate memory to stick all requests in and
 	 * send to server in one go.  Failing the allocation,
 	 * do it one by one.
 	 */
 
+	clears = marks = 0;
+
+	list_for_each_entry(fe, &flush_list, list) {
+		if (fe->type == DM_CLOG_MARK_REGION)
+			marks++;
+		else
+			clears++;
+	}
+	m = marks;
+	c = clears;
+	c_ptr = m_ptr = NULL;
+
+	if (marks > 1)
+		m_ptr = kmalloc(sizeof(*m_ptr)*marks, GFP_KERNEL);
+
+	if (clears > 1)
+		c_ptr = kmalloc(sizeof(*c_ptr)*clears, GFP_KERNEL);
+
 	list_for_each_entry(fe, &flush_list, list) {
-		r = cluster_do_request(lc, lc->uuid, fe->type,
-				       (char *)&fe->region,
-				       sizeof(fe->region),
-				       NULL, NULL);
+		if ((fe->type == DM_CLOG_MARK_REGION) && (m_ptr))
+			m_ptr[--m] = fe->region;
+		else if ((fe->type == DM_CLOG_CLEAR_REGION) && (c_ptr))
+			c_ptr[--c] = fe->region;
+		else
+			r = cluster_do_request(lc, lc->uuid, fe->type,
+					       (char *)&fe->region,
+					       sizeof(fe->region),
+					       NULL, NULL);
 		if (r)
 			goto fail;
 	}
 
+	if (m_ptr) {
+		/* If there is more than GROUP_SIZE, send in groups */
+		for (m = 0; m < marks; m += GROUP_SIZE) {
+			size = ((marks - m) > GROUP_SIZE) ? GROUP_SIZE : (marks - m);
+			size *= sizeof(*m_ptr);
+
+			r = cluster_do_request(lc, lc->uuid,
+					       DM_CLOG_MARK_REGION,
+					       (char *)(m_ptr + m), size,
+					       NULL, NULL);
+			if (r)
+				goto fail;
+		}
+	}
+
+	if (c_ptr) {
+		/* If there is more than GROUP_SIZE, send in groups */
+		for (c = 0; c < clears; c += GROUP_SIZE) {
+			size = ((clears - c) > GROUP_SIZE) ? GROUP_SIZE : (clears - c);
+			size *= sizeof(*c_ptr);
+
+			r = cluster_do_request(lc, lc->uuid,
+					       DM_CLOG_CLEAR_REGION,
+					       (char *)(c_ptr + c), size,
+					       NULL, NULL);
+			if (r)
+				goto fail;
+		}
+	}
+
 	r = cluster_do_request(lc, lc->uuid, DM_CLOG_FLUSH,
 			       NULL, 0, NULL, NULL);
 
@@ -441,6 +496,11 @@ fail:
 	 * Calling code will receive an error and will know that
 	 * the log facility has failed.
 	 */
+	if (m_ptr)
+		kfree(m_ptr);
+	if (c_ptr)
+		kfree(c_ptr);
+
 	list_for_each_entry_safe(fe, tmp_fe, &flush_list, list) {
 		list_del(&fe->list);
 		mempool_free(fe, flush_entry_pool);