On 25/03/13 04:39, Dave Reisner wrote: > On Sun, Mar 24, 2013 at 07:28:15PM +0100, Lukas Fleischer wrote: >> On Sun, Mar 24, 2013 at 11:26:04AM -0700, Anatol Pomozov wrote: >>> Hi >>> >>> On Sun, Mar 24, 2013 at 10:57 AM, Anatol Pomozov >>> <[email protected]> wrote: >>>> Hi, >>>> >>>> I am an update junkie. I do "pacman -Suy" several times a day. One >>>> thing I do not like with current pacman is that it redownloads whole >>>> index file each time I update system. >>>> >>>> :: Synchronizing package databases... >>>> core 104.4 KiB 104K/s 00:01 >>>> [######################] 100% >>>> extra 1416.9 KiB 171K/s 00:08 >>>> [######################] 100% >>>> community 1916.6 KiB 204K/s 00:09 >>>> [######################] 100% >>>> >>>> It is 3.5M it total even if only just a few new packages were added. >>>> Multiply 3.5M to number of users and you'll get a huge number. IMHO it >>>> is waste of bandwidth and user time. From other side index is >>>> incremental by it nature. Could pacman use index format that fits >>>> incremental updates better? >>>> >>>> A naive proposal is to use compressed format for "full fetch" (e.g. >>>> for users who did not update more than a week), and uncompressed >>>> append-only index for incremental. On incremental update client sends >>>> request to server "give me append file file starting from position XXX >>>> till the end of file", so only delta from the last update will be >>>> fetched. Then pacman applies the delta to client index. >>>> >>>> What do you think about this idea? >>> >>> Ok, found pacman.conf option "UseDelta" that seems does what I need. >>> BTW why it is not enabled by default? Isn't saving bandwidth a good >>> thing? >> >> I'm not sure whether "UseDelta" also affects package lists (rather than >> packages only). Arch Linux does not support deltas on the server side >> yet, see FS#18590 [1] for details. >> >> [1] https://bugs.archlinux.org/task/18590 > > UseDelta only affects packages. It's simply not feasible to create > deltas for the sync DBs as they exist today, especially over HTTP/FTP. >
To clarify - 10s if not 100s of packages get updated on an average day. That is a lot of deltas...
