On Thu, Sep 1, 2011 at 2:57 PM, Philipp Überbacher <[email protected]> wrote: > Excerpts from Karol Blazewicz's message of 2011-09-01 19:38:32 +0200: >> On Thu, Sep 1, 2011 at 7:33 PM, Philipp <[email protected]> wrote: >> > Hi there, >> > pacman works very well for me, with one exception: searching for >> > installed packages. For me a -Ss takes about 5 seconds, a -Qs 25 >> > seconds. I also noticed that this seems to be true for the first search >> > run only, the following ones are less than a second, no matter whether >> > it's a repo or local search. But if you want to just quickly find out a >> > thing, 25 seconds or so is a long time. >> > >> > Anyway, I had a very brief look at the code and am far from >> > understanding it, but I think libalpm/db.c handles the search, the >> > package names, descriptions, etc. are stored in a linked list of >> > structs, the whole thing is cached in memory only and regex wizardry >> > is used for the search. If that's true, the bottleneck I experience is >> > the caching. >> > >> > 5 seconds for -Ss is acceptable for me, but I wonder whether there's a >> > reasonably easy way to improve the 25 seconds of -Qs. >> > >> > My knowledge of pacman internals is non-existant and my C skills are >> > minimal, so I don't think I can be a lot of help with this one, but >> > maybe there's something else I can be of help with instead. >> > >> > Best regards, >> > Philipp >> > >> > >> > >> >> I'm getting 10s -Qs first-time searches, what harddrive are you using?? > > It's a normal laptop HD, Hitachi HTS54321, 160GB, 5400 rpm. > It's really kind of weird that the web search takes longer than the > local search, intuition dictates it should be the other way around.
It is not a web search, though. -Ss searches in /var/lib/pacman/sync and -Qs searches in /var/lib/pacman/local. Both are limited by the same I/O bus. Theoretically, you'll have less packages installed than not installed, so the size of /var/lib/pacman/local should be smaller than /var/lib/pacman/sync. Could you compare the sizes of those two directories? -- A: Because it obfuscates the reading. Q: Why is top posting so bad? ------------------------------------------- Denis A. Altoe Falqueto Linux user #524555 -------------------------------------------
