Ever since upgrading to Fedora 14 my desktop felt sluggish. It was more than the typical boiling frog kind of sluggishness, where you get the feeling everything’s snappy just after you bought a new fancy computer and install it freshly with a recent OS, and over time performance slowly degrades until you wonder why computers are always so slow. Sure, it looks like Evolution, after a round of improvements in memory management, has gone back to being a memory hog. But this time, it was more. It would go through short phases of unresponsiveness and then come back. Load would be consistently around 1 or more, but for no apparent reason at all.
After a while watching top, I noticed a process called kslowd[xxx] jumping up and down in the top output regularly. The k says it’s a kernel process. No idea what it is. Googling isn’t very helpful to learn what it actually is, but it did put me on the trail because there are huge amounts of posts on sites and mailing lists about this process eating CPU time and slowing down the computer.
After a bunch of reading some post suggested it might be this patch by Dave Airlie, a name I recognize, to the kernel. I took the Fedora kernel src.rpm, spent a few minutes getting acquainted with Fedora’s kernel spec layout de l’année, integrated the patch, rebooted, and voila. No more kslowd000 eating all my CPU.
I recently found this workaround which I’ll try next time the kernel gets upgraded.
That still doesn’t tell me what that kernel process is supposed to be doing (anyone up for a mandatory rule of having man pages for kernel processes too ?), so feel free to comment!