From mboxrd@z Thu Jan 1 00:00:00 1970 From: Priyanka Gupta Jain Subject: looking for something like raw_rwlock_t in Linux 3.0 Date: Thu, 3 May 2012 16:21:00 +0530 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE To: linux-rt-users Return-path: Received: from mail-gh0-f174.google.com ([209.85.160.174]:34709 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753981Ab2ECKvB convert rfc822-to-8bit (ORCPT ); Thu, 3 May 2012 06:51:01 -0400 Received: by ghrr11 with SMTP id r11so1585134ghr.19 for ; Thu, 03 May 2012 03:51:00 -0700 (PDT) Sender: linux-rt-users-owner@vger.kernel.org List-ID: hi, I am still looking for the answer to the below. I will be highly thankful if someone can help in it. Is there something like raw_rwlock_t in Linux3.0 which can make the rwlock_t behave in similar way as in RT disable. This might help me in solving throughput issue in 8-core system due to read/write lock. Regards Priyanka On Wed, Apr 11, 2012 at 10:32 AM, Priyanka Gupta Jain wrote: > hi, > > I am observing drastic throughput reduction in IPSEC traffic with RT > enable and disable. Throughput drops from 576 fps to 69fps. > Please note that I am using 8-core system with Linux 3.0.26-rt45 (SMP= ) > running on it. > > With the help of ftrace (function graph) in case of RT enable, I coul= d > see xfrm_policy_get_afinfo() and xfrm_policy_put_afinfo taking time() > sometimes taking time arounnd 1.43 msec and =A01.351msec respectively= =2E > > As in my test case, I was writing afinfo_policy before starting the > traffic without chainging in between, it was safe to remove read lock > and read unlock from xfrm_policy_get_afinfo() and > xfrm_policy_put_afinfo() functions. With the read lock/unlock removed= , > I could see throughput rising from 69fps to 133fps. > > Now I need your suggestions for the below: > 1) Removing the read lock is not a good way as the system might now > work properly in the real set-up. But with the change of read-write > lock to mutex by PREEMPT_RT patch, I am not able to fully utilize > 8-core system leading to drastic reduction in throughput. So what is > the suggested way to tackle this situation. > > 2) Even after removing the read lock, I could see the difference in > IPSEC thoughput in RT enable (133fps) and RT disable (576fps). Any > suggestion?. > > > Regards > Priyanka -- To unsubscribe from this list: send the line "unsubscribe linux-rt-user= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html