On Apr 4, 2005 4:44 PM, Volker Armin Hemmann <[EMAIL PROTECTED]> wrote: > Hi, > > On Monday 04 April 2005 10:55, Jose Gonzalez Gomez wrote: > > Hi there, > > > > I've been experiencing performance problems in my laptop (Acer Aspire > > 1522WLMi). I have the feeling that the problem is related to hard > > drive performance, as whenever I do some I/O intensive task (mainly > > tested compiling Java code) my system performance goes down, and > > switching to any other application takes a lot (hard drive performance > > problem while doing swapping?). I hasn't been able to solve it, > > although I've read doco and tried tweaking the hd peformance with > > hdparm. > > swap is incredibly slow on linux. As soon as you are hitting swap, your box is > dead slow. > > And this is not, because the swapping mechanism is stupid (it seems to be > stupid for me, because it always swaps out the wrong things), but because how > it reads the data back (if I remember right, there were some discussions on > lkml in january and february about low swap performance). > > For example: > I have 512mb ram, and this is enough. Really. But to be safe, I have 1gig > swap. > > So, I have KDE 3.4 with a lot of eye-candy running, some konqueror-windows > with tabs, kmail, swap is not used. > > I download BIGFILE (like some linux-isos), suddenly KDE is dead slow. Ok, the > harddisk is doing a lot of stuff, so it is normal for everything that wants > to load something is slow, but hey, the download has ended, BIGFILE lies > around on my harddisk, but KDE is still mostly swapped out and the > caches&buffers are huge(Reducing swappiness to 10 does not help)? What is > that? And why does it not get better over the next minutes/hours? > > How do I get my performance back? Easy: swapoff -a && swapon -a and bingo, KDE > is lighting fast again. > > Something is very broken in swapland, but at least the workaround is easy ...
I tried the swapoff/swapon command but took around a minute or so to complete in my machine, so I guess this may be a workaround in some situations, but it's not suitable in my case: I get the slowdown everytime I execute Maven to compile and deploy the application I'm developing in my local test environment. Deactivating and reactivating swap every time I compile would be overkill. I'm developing in Java/J2EE using Eclipse, Maven, JBoss and KDE, with 512Mb of main memory and 1Gb of swap. Assuming this is the problem, is there any other solution than buying a 1Gb memory module and throwing away one of my 256Mb modules (I have no free slot)??? Can't the swap performance be improved in any way? Thanks, best regards Jose -- gentoo-user@gentoo.org mailing list
