Messages in this thread | | | From | Tim Connors <> | Subject | Re: ~500 megs cached yet 2.6.5 goes into swap hell | Date | Fri, 30 Apr 2004 13:17:29 +1000 |
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Adam Kropelin <akropel1@rochester.rr.com> said on Thu, 29 Apr 2004 14:14:13 -0400: > On Wed, Apr 28, 2004 at 09:47:45PM -0400, Rik van Riel wrote: > > On Wed, 28 Apr 2004, Andrew Morton wrote: > > > > > OK, so it takes four seconds to swap mozilla back in, and you noticed it. > > > > > > Did you notice that those three kernel builds you just did ran in twenty > > > seconds less time because they had more cache available? Nope. > > > > That's exactly why desktops should be optimised to give > > the best performance where the user notices it most... ... > The 'swappiness' tunable may well give enough control over the situation > to suit all sorts of users. If nothing else, this thread has raised > awareness that such a tunable exists and can be played with to influence > the kernel's decision-making. Distros, too, should give consideration to > appropriate default settings to serve their intended users.
Actually, I decided to investigate how 2.4 compares (we're still stuck on 2.4)
According to this: http://www.uwsg.iu.edu/hypermail/linux/kernel/0210.1/0011.html
2.6 with swapiness of 0% is same as 2.4.19 - I assume 2.4.19's VM is the same as 2.4.26 (given feature freeze).
I have always been completely unimpressed with the 2.4 VM - before and after the big change in ~2.4.10. It has *always* preferred to use cache in preference to a recently used application.
So will this still apply to 2.6 with swapiness of 0%?
I might try to get my sysadmin to put on 2.6, becuase 2.4 is quite unusable for some of the work I do (if I need mozilla at the same time as my visualisation software, which allocates a good 3/4 of RAM, after reading a file that is about that size, leaving still enough for mozilla and X combined, mozilla and parts of X still get swapped out - and the cahce is wasted, since I only ever read the file once, and it is written on another host)
-- TimC -- http://astronomy.swin.edu.au/staff/tconnors/ "32-bit patch for a 16-bit GUI shell running on top of an 8-bit operating system written for a 4-bit processor by a 2-bit company who cannot stand 1 bit of competition." - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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