netdev - [PATCH 05/15] RDS: increase size of hash-table to 8K

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1442703892-26692-6-git-send-email-santosh.shilimkar@oracle.com>
Date:	Sat, 19 Sep 2015 19:04:42 -0400
From:	Santosh Shilimkar <santosh.shilimkar@...cle.com>
To:	netdev@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, davem@...emloft.net,
	ssantosh@...nel.org,
	Santosh Shilimkar <santosh.shilimkar@...cle.com>
Subject: [PATCH 05/15] RDS: increase size of hash-table to 8K

Even with per bucket locking scheme, in a massive parallel
system with active rds sockets which could be in excess of multiple
of 10K, rds_bin_lookup() workload is siginificant because of smaller
hashtable size.

With some tests, it was found that we get modest but still nice
reduction in rds_bind_lookup with bigger bucket.

	Hashtable	Baseline(1k)	Delta
	2048:		8.28%     	-2.45%
	4096:		8.28%		-4.60%
	8192:		8.28%		-6.46%
	16384:		8.28%		-6.75%

Based on the data, we set 8K as the bind hash-table size.

Signed-off-by: Santosh Shilimkar <ssantosh@...nel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@...cle.com>
---
 net/rds/bind.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rds/bind.c b/net/rds/bind.c
index bc6b93e..fb2d545 100644
--- a/net/rds/bind.c
+++ b/net/rds/bind.c
@@ -43,7 +43,7 @@ struct bind_bucket {
 	struct hlist_head	head;
 };
 
-#define BIND_HASH_SIZE 1024
+#define BIND_HASH_SIZE 8192
 static struct bind_bucket bind_hash_table[BIND_HASH_SIZE];
 
 static struct bind_bucket *hash_to_bucket(__be32 addr, __be16 port)
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html