Upgrading libcairo 1.0.4 to 1.2.0 we noticed that an application of ours,
run over an SSH connection with X forwarding enabled, is between 12 and 15 times
slower (hence unusable).
The application does intensive use of text rendering via gtksourceview and
gtkmathview. Investigating the reason, we realized that every application that
does intensive use of text rendering (e.g. gvim) is much slower too! (just open
with gvim a big file on a slow connection and you will see by yourself).
Comparing network traffic using our application, we noticed that:
1. the overall size of the exchanged packets with version 1.2.0 is only
slightly bigger than 1.0.4.
2. the overall number of exchanged packets with version 1.2.0 is about 6
We suspect 2 to be a possible cause because of the latency of every packet
during the roundtrip.
Other infos: we are actually running the testing version of Debian. The
phenomenon can be reproduced both on PC with hardware acceleration and on PC
Seems like the bug reported here:
Unnecessary Xflush calls are being made with cairo 1.2. Will be fixed in 1.2.2.
The fix for the XSync bug has now been pushed out into cairo "1.2.1":
Can you please test that that fix does indeed fix the problem you noticed? You
could do this by pulling the latest version of cairo from git, or else by
downloading the patch from the URL quoted above, and applying it.
If we don't hear feedback one way or the other by the time all the other blocker
bugs are fixed, then we'll assume that this bug is fixed and we'll release 1.2.2.
indeed the patch solves the problem. I think you can close this bug.
*** Bug 7724 has been marked as a duplicate of this bug. ***