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Show HN: wcp – a reimplementation of cp using io_uring. With a nice progress bar
- PaulHoule 6y agoI'd like to see more performance analysis. 10 years ago I found there was little benefit for async i/o to a disk, even though it great for networking. With SSD it coukd he different if you have a very long q depth, but he shows charts for copies over nfs where async i/o might find a lot of latency to hide.
- wheybags 6y agoThe chart is showing data from an NFS copy, but the listed speeds in the blog and on github[1] are from a copy on a local SSD. That is a bit confusing though, maybe I should make it more clear. I used the network copy for ETA calculation because it was an easy way to make the transfer take longer - if the whole copy is only a few seconds long it's difficult to meaningfully compare ETA estimation accuracy between two approaches. I would like to have more performance data though. 1: https://github.com/wheybags/wcp/#how-fast https://github.com/wheybags/wcp/#how-fast
- abvr 6y agoI would love to see a comparison between scp and wcp over NFS, more specifically large single file sizes, if folks are looking to discern more performance parameters. wcp is good stuff!
- wheybags 6y agoI would expect pretty much any plain copying program over NFS to beat scp, since scp has the overhead of encryption. On a slow disk with a fast CPU it might roughly match though.
- RMPR 6y agoThat's great stuff, I wonder how it compares to wdt[0] when there's only one TCP path. This has been my go-to tool to transfer files on the network. 0: https://github.com/facebook/wdt https://github.com/facebook/wdt
- wheybags 6y agoLooks like a cool project! There's no network functionality in wcp at the moment, but it's definitely something I'd consider adding in the future.