Stefan Sperling <s...@elego.de> writes: >> I disagree. >> >> Upgrade requires more disk IO but requires significantly less network IO >> and uses marginally less CPU. Checkout is likely to be faster when disk >> IO is the limiting factor, but if network IO is the limiting factor then >> checkout could be significantly slower. > > When I upgraded a 1.6.x working copy of 2GB size, it took more than one hour. > I eventually just aborted the upgrade. A checkout completes within > a couple of minutes. > > The repository is remote and the bottleneck should be my 16MB/s downstream > link (the server is connected to my ISP via the berlin internet exchange > at 100Mbit/s). So based on what you're saying I should be seeing a much > better upgrade vs. checkout ratio. > > Link to the repository: http://svn.dslinux.org/svn/trunk > > svn also seemed to spend more and more time hogging the CPU as the upgrade > progressed. Note: I have not profiled this, it is all based on what I > perceived while waiting for the upgrade to complete, and I kept box getting > more and more impatiant. I'd be willing to repeat this experiment with a > profiled build.
I don't know why that upgrade is slow, but perhaps you are limited by disk IO. Maybe upgrade doesn't scale properly. It's wrong to claim that checkout is faster than upgrade unconditionally. A checkout of Subversion trunk from Apache takes about 10s on my machine, an upgrade takes 5s. That's with a hot cache, with a cold cache upgrade takes about 15s. The checkout speed varies, sometimes it takes ove 20s. Which one is faster? -- Philip
