2024-09-25T03:08:00.689Z

<jcollin> snapdiff gives the list of files/dirs names that have changed in a directory tree.

2024-09-25T03:09:59.743Z

<jcollin> > I though it also included APIs for efficiently getting the delta of the actual file data which has changed
snapdiff doesn't have such API. Does the copy_file() does the file sync incrementally ? @Venky Shankar

2024-09-25T03:36:19.015Z

<gregsfortytwo> Well crap. I’ve been lying to people then :( I thought that was most of the point. (It’s definitely something we will need to add to the interface when we get there. Not sure how hard that will be, but I don’t think too much work.)

2024-09-25T03:38:39.315Z

<jcollin> Back then, I was just using the text that Igor Fedotov's snapdiff API returns.

2024-09-25T03:40:25.653Z

<jcollin> and then rewriting the incremental sync.

2024-09-25T03:40:52.171Z

<jcollin> and then rewriting the incremental sync in PeerReplayer.cc

2024-09-25T03:42:57.334Z

<jcollin> It just uses the text that Igor Fedotov's snapdiff API returns.

2024-09-25T03:43:21.034Z

<gregsfortytwo> there’s a random question about rbd snap diffs in <#C1HFZTW81|> which led me to looking at libcephfs snapdiff, and I’m confused: does snapdiff only tell you files which have changed between snapshots? I though it also included APIs for efficiently getting the delta of the actual file data which has changed, but am not seeing it.

2024-09-25T08:53:15.898Z

<Dhairya Parmar> @gregsfortytwo @jcollin I think the feature to get the delta of all the files between two snapshot exists, it's written by croit <https://croit.io/blog/cephfs-snapdiff-feature>

2024-09-25T09:27:58.557Z

<Venky Shankar> Yeh, its just the list of file name diffs. I actually put this up explicitly in the BZ QE raised.

2024-09-25T12:19:29.473Z

<jcollin> That is Igor's code. By delta they mean file/dir names only.

2024-09-25T12:23:11.592Z

<Dhairya Parmar> oh

2024-09-25T12:54:48.553Z

<Venky Shankar> Looks like my n/w went really bad right at the end of the standup. Sorry for that!

2024-09-25T13:09:10.584Z

<Mark Nelson (nhm)> @Venky Shankar heya, I saw you've been investigating caps release latency issues lately.  Just wanted to say great work!

2024-09-25T13:11:39.619Z

<Venky Shankar> Not entirely on my own - thanks for everyone involved 👍

2024-09-25T13:16:05.620Z

<Mark Nelson (nhm)> Btw, I've had a suspicion that especially on larger memory systems we may be seeing caps release time jitter from the linux page cache so I've been doing more testing lately with Jeff's nopagecache option.  Do we keep any counters of average/tail caps release times?

2024-09-25T16:04:05.988Z

<Patrick Donnelly> no

2024-09-25T16:04:10.847Z

<Patrick Donnelly> we should though