From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from penguin.e-mind.com (penguin.e-mind.com [195.223.140.120]) by kvack.org (8.8.7/8.8.7) with ESMTP id KAA30390 for ; Tue, 22 Dec 1998 10:57:35 -0500 Date: Tue, 22 Dec 1998 16:40:26 +0100 (CET) From: Andrea Arcangeli Reply-To: Andrea Arcangeli Subject: Re: New patch (was Re: [PATCH] swapin readahead v3 + kswapd fixes) In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: "Eric W. Biederman" Cc: Linus Torvalds , "Stephen C. Tweedie" , Rik van Riel , Linux MM , Alan Cox List-ID: On 22 Dec 1998, Eric W. Biederman wrote: >My suggestion (again) would be to not call shrink_mmap in the swapper >(unless we are endangering atomic allocations). And to never call >swap_out in the memory allocator (just wake up kswapd). Ah, I just had your _same_ _exactly_ idea yesterday but there' s a good reason I nor proposed/tried it. The point are Real time tasks. kswapd is not realtime and a realtime task must be able to swapout a little by itself in try_to_free_pages() when there's nothing to free on the cache anymore. Since I agree with you to run mainly shrink_mmap() in the foreground freeing I just proposed yesterday to use an higher priority in try_to_free_pages (see my patch, it starts with priority = 4, Linus's now start with prio = 5). This way we are pretty sure that the foreground freeing will be done in shrink_mmap() and so that some memory will be really freed some way (and this will avoid also tasks other than kswapd to sleep waiting for slowww SYNC IO). I agree with you with the argument that it's a bogus architecture to use in the same way the actual swap_out and shrink_mmap() since swap_out doesn' t really free pages.... Linus's pre-4 seems to work well here though... Andrea Arcangeli -- This is a majordomo managed list. To unsubscribe, send a message with the body 'unsubscribe linux-mm me@address' to: majordomo@kvack.org