linux-kernel - Re: [PATCH 00/30] PREEMPT_AUTO: support lazy rescheduling

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 for Android: free password hash cracker in your pocket

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

Message-ID: <af122806-8325-4302-991f-9c0dc1857bfe@amd.com>
Date: Thu, 22 Feb 2024 18:34:33 +0530
From: Raghavendra K T <raghavendra.kt@....com>
To: Thomas Gleixner <tglx@...utronix.de>,
 Ankur Arora <ankur.a.arora@...cle.com>, linux-kernel@...r.kernel.org
Cc: peterz@...radead.org, torvalds@...ux-foundation.org, paulmck@...nel.org,
 akpm@...ux-foundation.org, luto@...nel.org, bp@...en8.de,
 dave.hansen@...ux.intel.com, hpa@...or.com, mingo@...hat.com,
 juri.lelli@...hat.com, vincent.guittot@...aro.org, willy@...radead.org,
 mgorman@...e.de, jpoimboe@...nel.org, mark.rutland@....com, jgross@...e.com,
 andrew.cooper3@...rix.com, bristot@...nel.org,
 mathieu.desnoyers@...icios.com, geert@...ux-m68k.org,
 glaubitz@...sik.fu-berlin.de, anton.ivanov@...bridgegreys.com,
 mattst88@...il.com, krypton@...ich-teichert.org, rostedt@...dmis.org,
 David.Laight@...LAB.COM, richard@....at, mjguzik@...il.com,
 jon.grimm@....com, bharata@....com, boris.ostrovsky@...cle.com,
 konrad.wilk@...cle.com
Subject: Re: [PATCH 00/30] PREEMPT_AUTO: support lazy rescheduling

On 2/21/2024 10:45 PM, Thomas Gleixner wrote:
> On Wed, Feb 21 2024 at 17:53, Raghavendra K T wrote:
>> Configuration tested.
>> a) Base kernel (6.7),
> 
> Which scheduling model is the baseline using?
> 
>> b) patched with PREEMPT_AUTO voluntary preemption.
>> c) patched with PREEMPT_DYNAMIC voluntary preemption.
>>
>> Workloads I tested and their %gain,
>>                      case b                   case c
>> NAS                +2.7                    +1.9
>> Hashjoin,          +0			     +0
>> XSBench	     +1.7		     +0
>> Graph500,  	     -6 		     +0
> 
> The Graph500 stands out. Needs some analysis.
> 

Hello Thomas, Ankur,

Because of high stdev I saw with the runs for Graph500, continued to 
take results with more iterations.

Here is the result. It does not look like there is a concern here.

(you can see the *min* side of preempt-auto case which could have got 
the negative result in the analysis, But I should have posted stdev 
along with that. Sorry for not being louder there.).

Overall this looks good. some time better but all within noise level.

Benchmark = Graph500

x  6.7.0+
+  6.7.0-preempt-auto+

     N           Min           Max        Median           Avg        Stddev
x  15 6.7165689e+09 7.7607743e+09 7.2213638e+09 7.2759563e+09 3.3353312e+08
+  15 6.4856432e+09  7.942607e+09 7.3115082e+09 7.3386124e+09 4.6474773e+08

No difference proven at 80.0% confidence
No difference proven at 95.0% confidence
No difference proven at 99.0% confidence

Thanks and Regards
- Raghu