yum-presto not on by default
Bill Nottingham
notting at redhat.com
Thu Sep 24 05:05:19 UTC 2009
Jonathan Dieter (jdieter at gmail.com) said:
> The second one has to do with the fact that when rebuilding the rpms, we
> have to recompress the data, and xz compression is over 10x slower than
> gzip.
Stats of the day...
I took an existing xz-compressed RPM, and built a newer release of that
package with varying xz levels. The numbers are:
- the new package size at that XZ compression level
- the time to create a new deltarpm from a delta to that new version
level 1
1416k
real 0m0.935s
user 0m0.893s
sys 0m0.036s
level 2
952k
real 0m0.839s
user 0m0.790s
sys 0m0.048s
level 3
848k
real 0m2.762s
user 0m2.702s
sys 0m0.055s
level 4
832k
real 0m2.902s
user 0m2.817s
sys 0m0.084s
level 5
824k
real 0m3.269s
user 0m3.131s
sys 0m0.128s
level 6
812k
real 0m4.364s
user 0m4.026s
sys 0m0.164s
level 7 (what we do now)
812k
real 0m4.698s
user 0m4.516s
sys 0m0.176s
So... just set the xz compression level to 2, let it be that way for future
builds, and go about our business?
Bill
More information about the fedora-devel-list
mailing list