Reiserfs and Compiling: HEAVY RAM usage + swapping?!?

jdong · n00b Joined: 01 Mar 2004 Posts: 41

I've been trying out various filesystems recently, and last week it was reiser. Traditionally, I've been a 100% XFS fan, but I decided to "see the rest of the world".

Reiser feels faster than XFS when copying files, emerge sync'ing, and emerge searching.

(or so I thought).

Yesterday, I was emerging packages in the background, while writing a presentation in the foreground. I had Ximian OOo Impress and Firefox started. I temporarily ALT-TABbed to Firefox to research, and 30 secs later, when alt tabbing back, I noticed Impress was unusually SLOW to respond. It must've took 10 seconds to fully load my slide! (Mixed multi-picture)

Then, I pulled up a terminal, issued free -m.

Free reports 502 total, 322 used, 280 as buffer. However, it reports <b>120MB</b> of swap used!

Huh, that's strange. I issued it again. Swap usage is steadily climbing.

So, I decided to launch Thunderbird, to see how the cache reacts to heavier RAM demands. Amazingly, the 280MB stayed almost constant, dropped only a megabyte or 2, and SWAP kept rising. The kernel swapped out Impress and Thunderbird.

I turned off swap. The cache fell, and after it finished unswapping, the system behaved quite normally.

I remade the swap, turned it on again. The swap instantly starts to fill up.

I thought it must have been my kernel (2.6.7-gentoo-r11), but then I tried mm and ck kernels, they all acted the same way.

I was getting freaked out at this point, so I went on my Knoppix CD, re-formatted & reloaded XFS on my drives, and went back into Gentoo. I started the same emerge again.

Up to now, I can't reproduce the same issue XFS or ext3fs. free reports 450MB of 502 used, 320 as cache, and only 57MB of swap used. I have FF, Thunderbird, GAIM, KGPG, Impress, and emerge -uDv world going right now, and all my apps feel fast.

Anyone else have similar problems with Reiser?

jdgill0 · Posted: Sat Jul 24, 2004 4:39 am Post subject:

I read the following somewhere, but can I can not think at this time where that might have been. I had posted this to a friend, and hence he sent it back to me ... the following was recent news.

radonsg · Posted: Sat Jul 24, 2004 7:27 am Post subject:

jdong, which version of ReiserFS u using? Version3 or 4? I'm been using ReiserFS ver 3 for sometime, never experience your problem at all. High ram usage is common but my 1G swap was hardly utilised at all.

John5788 · Posted: Sat Jul 24, 2004 7:42 am Post subject: