Re: [SLE] clearing unused RAM, system performance
[snipped theory about updatedb/locate/reiserfs causing SWAP use]
"Fred A. Miller"
True, however, it's the ONLY file system I use, and I don't have that problem on any box.
But do you use updatedb and locate on those boxes? (I just threw in the mention of reiserfs because it seems to be much more likely to hang onto the mostly useless directory cache that updatedb fills up. Worse, it appears to do so in a way that looks suspiciously like a memory leak. Here is the memory use for my machine that runs updatedb every night, which I have not used much since last rebooting it and which has practically nothing running on it at the moment: markgray@mmx:~> free total used free shared buffers cached Mem: 255388 248264 7124 0 55404 65764 -/+ buffers/cache: 127096 128292 Swap: 530136 28752 501384 markgray@mmx:~> and here is a machine that does NOT run updatedb, with the same amount of memory, that I use very heavily and which is running a lot of memory hungry processes at the moment: markgray@k6:~> free total used free shared buffers cached Mem: 255960 239780 16180 0 53752 72572 -/+ buffers/cache: 113456 142504 Swap: 1228944 0 1228944
On Tue, 2003-05-13 at 11:54, Mark Gray wrote:
[ Worse, it appears to do so in a way that looks suspiciously like a memory leak. <snip> Here is the memory use for my machine that runs updatedb every night,
Heh, that's what I was thinking was wrong...a memory leak. Updatedb using all of this would make sense, especially since my swap doesn't get used until a day or so after I boot, which would have given cron enough time to run it over night. Well, I just checked both of my boxes that don't have "locate" installed, and they look similar to your boxes, % wise anyway. And neither of them are touching their cache, despite only having 96MB, and 256MB. Well, guess I'll uninstall "locate" on this machine, and see what happens if I don't log out for another 80 days ;) Thanks, -John -=JericAtSbcglobalDotNetwork=- 85 days 17 hrs 34 min, since last reboot. Did you know ... Firewalls, NATs, VPN, WindowsXP, and many other security/networking tools are technically ILLEGAL in the states of DE, IL, MD, MI, WY, PA, MA and VA. Stop the insanity, before its too late! (http://www.freedom-to-tinker.com/superdmca.html for links to the laws)
* Jeric (jeric@sbcglobal.net) [030513 11:05]: ->On Tue, 2003-05-13 at 11:54, Mark Gray wrote: ->> [ ->> Worse, it appears to do so in a way that looks suspiciously like a ->> memory leak. -><snip> ->> Here is the memory use for my machine that runs updatedb every night, -> ->Heh, that's what I was thinking was wrong...a memory leak. -> ->Updatedb using all of this would make sense, especially since my swap ->doesn't get used until a day or so after I boot, which would have given ->cron enough time to run it over night. Well, I just checked both of my ->boxes that don't have "locate" installed, and they look similar to your ->boxes, % wise anyway. And neither of them are touching their cache, ->despite only having 96MB, and 256MB. -> ->Well, guess I'll uninstall "locate" on this machine, and see what ->happens if I don't log out for another 80 days ;) Having cron running and updating the locate db should have absolutely no effect on this. I have cron turned off on my workstation in the office. So I run updatedb by hand every once and a while...not from cron. I still see 8.1 (Using 2.4.20) shoving things into swap. I watched it dump 45M of data into swap at once the otherday...it was weird. I just turned off swap all together. I have enough ram in the machine that I shouldn't need swap. -- Ben Rosenberg ---===---===---===--- mailto:ben@whack.org The IQ and the life expectancy of the average American recently passed each other going in the opposite direction.
45M of data into swap at once the otherday...it was weird. I just turned off swap all together. I have enough ram in the machine that I shouldn't need swap.
"Shouldn't need swap" and "Can't make good use of swap" are two different things. The more virtual memory the box has, the better. Turn your swap back on - Linux is designed to run with swap and the VM is tuned to use it. Just because you don't understand it, doesn't mean it's bad when it gets used! -- "...our desktop is falling behind stability-wise and feature wise to KDE ...when I went to Mexico in December to the facility where we launched gnome, they had all switched to KDE3." - Miguel de Icaza, March 2003
* Derek Fountain (derekfountain@yahoo.co.uk) [030513 18:05]: ->> 45M of data into swap at once the otherday...it was weird. I just turned ->> off swap all together. I have enough ram in the machine that I shouldn't ->> need swap. -> ->"Shouldn't need swap" and "Can't make good use of swap" are two different ->things. The more virtual memory the box has, the better. Turn your swap back ->on - Linux is designed to run with swap and the VM is tuned to use it. Just ->because you don't understand it, doesn't mean it's bad when it gets used! -> Don't ass-u-me I don't know what swap is used for...that's very rude and if you had a clue what I actually do for a living you'd keep comments like that your self ya wanker. With 1G of DDR333 ram I DO NOT need swap. I suppose since Mads told me he does use swap either that next you tell him he knows nothing of how the Linux kernel works. I won't turn my swap back on because it isn't needed. Without swap on I've never even gone above 300M of memory used. And no..the statement about having more swap the better is a load of bunk...it's Microsoft thinking at it's best. Having more physical ram is always better. Try running a box with 128M of ram and a gig of swap vs having 128M swap and a gig ram...which do you think will be faster. pfft. -- Ben Rosenberg ---===---===---===--- mailto:ben@whack.org The IQ and the life expectancy of the average American recently passed each other going in the opposite direction.
On Wednesday 14 May 2003 03:20, Ben Rosenberg wrote:
With 1G of DDR333 ram I DO NOT need swap.
http://www.ussg.iu.edu/hypermail/linux/kernel/0207.0/0320.html Perhaps not the best link out there, but lmkl is full of stuff like that. It's very interesting stuff.
I suppose since Mads told me he does use swap either that next you tell him he knows nothing of how the Linux kernel works. I won't turn my swap back on because it isn't needed. Without swap on I've never even gone above 300M of memory used.
Used for processes, you mean? But you're not getting the most out of your system, since you're not caching as much disk as you can
participants (5)
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Anders Johansson -
Ben Rosenberg -
Derek Fountain -
Jeric -
Mark Gray