Re: Fresh checkout vs 'svn upgrade': How good is good enough?

Paul Burba <ptburba_at_gmail.com> writes:

> No surprise that your checkouts are faster than mine given you are
> using a local mirror. What's puzzling me is why my upgrades are so
> much slower than yours.
>
> Running an upgrade of a trunk WC on my machine under xperf takes
> 00:03:46.351 elapsed and 11.44s CPU time using my primary drive (320
> GB, SATA-II, 7200 rpm, 16 MB Cache, NTFS). Subversion spends 50s
> total disk service time (46.8s of that is read service time).

Does "total disk service time" represent all the time waiting for disk
IO? 11s CPU plus 50s disk still leaves 165s unaccounted. Upgrade
prints a notification line for each directory, is there a significant
delay before the first line, or after the last line, or is the delay
spread among the lines?

If it is a Subversion problem rather than your machine there are two
areas that may be worth investigating (but it's hard to say when most of
the time is unaccounted).

The property migration currently invokes multiple transactions
per-directory. Moving to a single transaction per-directory will
probably help.

Upgrade currently copies all the text-bases, I did experiment with
creating workqueue items to move them instead but it wasn't any faster
on my Linux box. However it may help on Windows.

-- 
Philip