Hello,
I'm noticing significant sluggishness when switching into a workspace
where Evolution is running.
My kernel is Fedora 12's 2.6.32.16-150.fc12.x86_64 (I know it is
old...), and the open source radeon (r600) driver is used. Oprofile
shows the follows:
CPU: Core 2, speed 2003 MHz (estimated)
Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a
unit mask of 0x00 (Unhalted core cycles) count 100000
Counted INST_RETIRED_ANY_P events (number of instructions retired) with
a unit mask of 0x00 (No unit mask) count 100000
samples % samples % image name app name
symbol name
126807 31.2201 38744 28.3866 vmlinux Xorg
(deleted) find_vma
48661 11.9804 3474 2.5453 vmlinux Xorg
(deleted) mls_compute_sid
41806 10.2927 5700 4.1762 vmlinux Xorg
(deleted) sidtab_search_context
11888 2.9268 4234 3.1021 Xorg (deleted) Xorg
(deleted) /usr/bin/Xorg (deleted)
8660 2.1321 1589 1.1642 drm Xorg
(deleted) /drm
6228 1.5333 6773 4.9624 radeon Xorg
(deleted) /radeon
6214 1.5299 1832 1.3423 libc-2.11.2.so (deleted) Xorg
(deleted) /lib64/libc-2.11.2.so (deleted)
5542 1.3644 4929 3.6113
libpixman-1.so.0.16.6.#prelink#.3I5wow (deleted) Xorg
(deleted) /usr/lib64/libpixman-1.so.0.16.6.#prelink#.3I5wow
(deleted)
4149 1.0215 1776 1.3012 libexa.so Xorg
(deleted) /usr/lib64/xorg/modules/libexa.so
4140 1.0193 640 0.4689 vmlinux oprofiled
mls_compute_sid
3183 0.7837 847 0.6206 vmlinux Xorg
(deleted) arch_get_unmapped_area_topdown
...
Although I haven't looked into it, presumably Evolution is asking the X
server to create and map a lot of TTM objects (pixmaps?). The creation
of each object uses shmem_file_setup() and thus necessitates SELinux
calls, and since the X process already has a lot of mappings (one
mapping for each XRender glyph it seems, with "wc -l /proc/`pgrep
Xorg`/maps" returning 6766), the mapping part could also be slow.
I think the slowness of find_vma is related to
https://bugzilla.kernel.org/show_bug.cgi?id=17531 . mls_compute_sid()
did a linear search over the range transition rules and was therefore
slow, but more recent kernels use a hash table so this problem has been
solved. Another offender is sidtab_search_context() used to convert a
SELinux context back into an sid, which is also a linear search as there
is only a sid => context hash table, and I haven't seen any recent
changes in this area.
Please CC me as I'm not subscribed.
r6144
r6144 <[email protected]> writes:
> Hello,
>
> I'm noticing significant sluggishness when switching into a workspace
> where Evolution is running.
Interesting result. Adding some relevant ccs with full-quote.
I guess graphics really should do less mmaps, but the underlying
performance problems should be investigated too.
-Andi
>
> My kernel is Fedora 12's 2.6.32.16-150.fc12.x86_64 (I know it is
> old...), and the open source radeon (r600) driver is used. Oprofile
> shows the follows:
>
> CPU: Core 2, speed 2003 MHz (estimated)
> Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a
> unit mask of 0x00 (Unhalted core cycles) count 100000
> Counted INST_RETIRED_ANY_P events (number of instructions retired) with
> a unit mask of 0x00 (No unit mask) count 100000
> samples % samples % image name app name
> symbol name
> 126807 31.2201 38744 28.3866 vmlinux Xorg
> (deleted) find_vma
> 48661 11.9804 3474 2.5453 vmlinux Xorg
> (deleted) mls_compute_sid
> 41806 10.2927 5700 4.1762 vmlinux Xorg
> (deleted) sidtab_search_context
> 11888 2.9268 4234 3.1021 Xorg (deleted) Xorg
> (deleted) /usr/bin/Xorg (deleted)
> 8660 2.1321 1589 1.1642 drm Xorg
> (deleted) /drm
> 6228 1.5333 6773 4.9624 radeon Xorg
> (deleted) /radeon
> 6214 1.5299 1832 1.3423 libc-2.11.2.so (deleted) Xorg
> (deleted) /lib64/libc-2.11.2.so (deleted)
> 5542 1.3644 4929 3.6113
> libpixman-1.so.0.16.6.#prelink#.3I5wow (deleted) Xorg
> (deleted) /usr/lib64/libpixman-1.so.0.16.6.#prelink#.3I5wow
> (deleted)
> 4149 1.0215 1776 1.3012 libexa.so Xorg
> (deleted) /usr/lib64/xorg/modules/libexa.so
> 4140 1.0193 640 0.4689 vmlinux oprofiled
> mls_compute_sid
> 3183 0.7837 847 0.6206 vmlinux Xorg
> (deleted) arch_get_unmapped_area_topdown
> ...
>
> Although I haven't looked into it, presumably Evolution is asking the X
> server to create and map a lot of TTM objects (pixmaps?). The creation
> of each object uses shmem_file_setup() and thus necessitates SELinux
> calls, and since the X process already has a lot of mappings (one
> mapping for each XRender glyph it seems, with "wc -l /proc/`pgrep
> Xorg`/maps" returning 6766), the mapping part could also be slow.
>
> I think the slowness of find_vma is related to
> https://bugzilla.kernel.org/show_bug.cgi?id=17531 . mls_compute_sid()
> did a linear search over the range transition rules and was therefore
> slow, but more recent kernels use a hash table so this problem has been
> solved. Another offender is sidtab_search_context() used to convert a
> SELinux context back into an sid, which is also a linear search as there
> is only a sid => context hash table, and I haven't seen any recent
> changes in this area.
>
> Please CC me as I'm not subscribed.
>
> r6144
>
--
[email protected] -- Speaking for myself only.