linux-kernel - Re: Suggested code change : Simple : Scale pdflush threads from desktop to server

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: <2AF5E97B-E5D6-4302-9C13-30B2270F15D3@earthlink.net>
Date:	Fri, 10 Jul 2009 18:48:39 -0700
From:	Mitchell Erblich <erblichs@...thlink.net>
To:	Mitchell Erblich <erblichs@...thlink.net>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: Suggested code change : Simple : Scale pdflush threads from desktop to server

Sorry,

	IF Not rate limit. Missing not / !.
	if (!(printk_ratelimit() )) {


	Mitchell Erblich	
	================
	
On Jul 10, 2009, at 6:25 PM, Mitchell Erblich wrote:

> Group,
>
> 		pdflush threads clean dirty pages
>
> 	  Under the past simple assumption that a greater number of
> 	  page daemon threads will have the TENDENCY to clean
> 	  the pages faster.
>
> 	Another assumption is that a server will have at least 2x / 4x the
> 	number of drives and memory, so allocating more pdflush() threads
> 	makes sense.
>
> 	Relying on a recent change, code base on whether the system is
> 	a desktop or a server, scale the number of pdthreads() which would
> 	result in the below code change.
>
> 	The suggestion is to double the MIN number of threads and set the
> 	MAX number to 4x.
>
> 	./mm/pdflush.c
> 	/* Scale for a server */
> 	#define MIN_PDFLUSH_THREADS 	4		/* 2x desktop value */
> 	#define MAX_PDFLUSH_THREADS 	32		/* 4x desktop value */
>
>
> 	/*
> 	 * secondary suggestion is to add a DEBUG type /var/log/system  
> messages that
> 	 * will rate limit independent of desktop or server.
>         */
>
> 	else if (nr_pdflush_threads == MAX_PDFLUSH_THREADS) {
> 		   /* optional PDFLUSH msg */
> 		   if (printk_ratelimit() {
> 	 		                            printk(KERN_INFO  
> "MAX_PDFLUSH_THREADS Limited\n");
>                   }
>         }
> 	
>
> 	

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/