Leen Besselink wrote: > Daniel.Li wrote: >> Dear List, >> >> I'm trying to take a closer look at rsync code, and found when we run >> daemon, it will take a lot of CPU (400Mhz). So I'm interested in Which >> part of rsync code on ver 3.0.5 consuming CPU a lot? >> >> Can anyone here help to lighten me up? So I can try to improve the >> performance or low the CPU usage. >> >> >> I suspect that there are a few factors, which might related with CPU >> usage: rolling checksum/Disk IO(a slide window has been implemented), >> read or write? >> >> >> Hope I can find some info here! Thanks in advance! >> >> > > Hi Daniel, > > Not sure how much you know about how rsync works, but maybe you first want > to know how the algoritm works ? I'm fairly sure it's a large part of the > CPU-usage: > > http://www.samba.org/rsync/tech_report/ > > But I personally enjoyed the talk talk Andrew Tridgell did at OLS in 2000 > more, here is a transcript: > > http://olstrans.sourceforge.net/release/OLS2000-rsync/OLS2000-rsync.html > > Here are the slides of the talk: > > ftp://ftp.samba.org/pub/tridge/talks/rsync_ols.tgz > > I wouldn't be surprised if you were able to find the mp3 online somehere > with the filename: > > 2000-07-21_15-02-49_C_64.mp3 > >
I was checking the talk and did find this bit: "in fact the bottleneck, when people use the -z option, 90% of the CPU is in gzip, you know, the zlib library." So if you enabled compression, then you probably know where your CPU-time went. -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
