On 11/02/2014 13:07, Walter Dnes wrote: > On Tue, Feb 11, 2014 at 07:32:46AM +0200, Alan McKinnon wrote > >> emerge --sync X number of times daily in a cron >> >> emerge -avuND world deliberately and manually as the sysadmin at your >> leisure. >> >> Two different actions in time. > > Assume you sync once a day, and update once a week, the first 6 syncs > would be mostly wasted. Yes, your final sync would be smaller. But > your machine and the server would have to go through the file-comparison > process 7 times, instead of once. >
So what? rsync is cheap and doesn't stress the server unduly. It doesn't check every object in the directory tree and stat 179680 files/dirs every time, the whole thing is hashed and it's the hash values that are compared. To compare a directory, rsync only needs to look at the directory inode, if they match on both ends then it's a certainty the files match. It's a *very* efficient system, all done in-memory, your average server can deal with many connections and not even break a sweat. If you want to minimize load, concentrate on making emerge world more efficient so that it takes less than 3 minutes to depgraph on a fast cpu and up to 40 on a slow one. Coupled with overlays, more often than not the portage cache is invalidated so emerge ends up sourcing almost every ebuild file in the tree. --sync is not something worth optimizing if done once a day. At that frequency you are well below the noise floor -- Alan McKinnon alan.mckin...@gmail.com
