Hi Zito, > Hello, > I faced the problem of synchronization block devices and found the patch > write-devices.diff by Darryl Dixon, that went trough this mailing list > http://lists.samba.org/archive/rsync/2009-October/024037.html > > Unfortunately the patch was one flaw for me. It doesn't improve > performance of synchronization. When I tried to test it using something > like:
Yes. I figured it would be something to do with the block device size calculation, as my initial patch simply punted on that (0 as you saw) - I didn't have time/motivation to dig through and research the necessary magic to get good data out. Well done for finding and implementing the required code :) > > ./rsync --rsync-path\="$PWD/rsync" -v --bwlimit=100 --progress > --copy-devices --write-devices /dev/mapper/vg-pokus1 > r...@localhost:/dev/mapper/vg-pokus2 > > where pokus1 & pokus2 are two identically initialized block devices > (logical volumes) 32MiB in size. All the data was passed trough > local connection without the benefit. (I set --bwlimit low, so I can see > evidently the rsync performance). > > By adding more -v I found, that some stat() call in the generator.c > reports destination device size is zero. I added some code handling > block device size. Option --ignore-times is implied for --rw-devices. > A new patch rw-devices.diff is attached. It is combination of > copy-devices.diff, write-devices.diff and some new code from me. Excellent stuff. This is what I love about open source software - one person can get the ball rolling and then the effort and expertise of others combines to improve matters for everyone. > Now I have questions: > 1. Is it worth to have two separate patches copy-devices.diff, > write-devices.diff? (It is hard to apply them one after other, > because they overlays.) > 2. Should be there two options `--copy-devices', `--write-devices'? > I thing one option e.g. `--rw-devices' should be sufficient. > 3. I think the above option should collide with many other options > like `--archive', `--recursive',... I agree maintaining the separate patches are hard. Personally, I'd prefer to see just one merged patch as you suggest. regards, Darryl Dixon Winterhouse Consulting Ltd http://www.winterhouseconsulting.com -- 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