30160 - improve font lookup performance on Unix

Status: VERIFIED FIXED

(Core :: Layout, defect, P3)

Description

[Erik van der Poel]

We need to get rid of the expensive XListFontsWithInfo calls. From bug 14961:

------- Additional Comments From [e-mail]  2000-03-02 16:28 -------
http://www.linux.com/ runs quite slow due to font querying on Unix.
Timing performed with a 3/2 morning cvs pull compiled with
--disable-debug --enable-optimize --enable-x11-shm.  The test machine
was a Sun Ultra-10 (440Mhz/afb) running Solaris 2.7.  viewer was
started with "about:blank", then "http://www.linux.com/" typed into
the url entry box.

                start   end     elapsed
viewer           0:02    0:03   0:01
Xsun            96:57   97:26   0:29
wall time                       0:36

Examining an xscope log of a similar session, I see three groups
of continuous ListFontsWithInfo calls amounting for about 28 seconds
worth of load time.

start load ~ 29.56s
ListFontsWithInfo       30.51-31.42     ~15 calls
ListFontsWithInfo       31.72-57.15     ~180 calls
ListFontsWithInfo       58.25-59.97     ~12 calls
finish load ~ 67.46s

Comment 1

[tor]

Attachment: replace frequent XListFontsWithInfo with XListFonts

Comment 2

[tor]

It turns out all the calls to XListFontsWithInfo in this test
were coming from nsDeviceContextGTK::CheckFontExistence, which
never used the font struct that was returned.  A simple replacement
with XListFonts sped things up immensely.  The same test as before
now runs like this:

                start   end     elapsed
viewer            0:02    0:03  0:01
Xsun            110:05  110:06  0:01
wall time                       0:05

Could you review the patch for checkin?

Comment 3

[tor]

Meant to assign this to myself with the last change.

Comment 4

[Christopher Blizzard (:blizzard)]

We should so check this in.  r=blizzard

Comment 5

[Erik van der Poel]

r=erik

Comment 6

[Phil Peterson]

[PDT+] w/b minus on 3/6

Comment 7

[Erik van der Poel]

tor, please check this in before 3/6! Thanks.

Comment 8

[tor]

Patch checked in.

Comment 9

[Chris Petersen]

Since I can't get access to a machine mentioned, Erik could you please mark this 
as verified ? Thanks.

Comment 10

[Erik van der Poel]

Although tor was using a Sun box, the code change was in an area that affects
all Unixes, including Linux. Petersen, do you have access to a Linux box?

Comment 11

[Chris Petersen]

Yes, I will check with latest build on Linux Redhat.

Comment 12

[Chris Petersen]

With the March 9th build (2000030913), this problem is resolved.