Bug 1780965

Summary:	Hang at startup in gtk2 apps
Product:	[Fedora] Fedora	Reporter:	Tom Horsley <horsley1953>
Component:	gtk2	Assignee:	Matthias Clasen <mclasen>
Status:	CLOSED WORKSFORME	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	31	CC:	caillon+fedoraproject, gnome-sig, john.j5live, mclasen, mkasik, rhughes, rstrode, samuel-rhbugs, sandmann
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Last Closed:	2019-12-14 18:37:45 UTC	Type:	Bug
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Description Tom Horsley 2019-12-08 19:39:21 UTC

Description of problem:

I have a feeling this is really a glibc problem, but since I only notice it
in gtk2 apps, that's where I'm reporting the bug.

The two examples I've noticed so far:

The claws-mail app hangs for 25 seconds on startup.
The gkrellm app hangs for 25 seconds when I first ask for the config dialog.

This sure appears to be related to the new computer I have with an Intel
i9-9900K cpu. Before you scoff, look at my evidence:

I make a fedora 31 virtual machine from the live cd. I install claws-mail
on it. It also hangs in this pristine new environment.

I then shutdown the virtual machine, configure the cpu model to be
IvyBridge and reboot.

Miracle of miracles! claws-mail no longer hangs when I start it.

I'm tempted to guess that some version of one of the optimized gnu-indirect
low level function is glibc is actually broken on the i9-9900K (or works
different and the way gtk2 is calling it is broken). But those are just
theories I don't have the resources to investigate.

Version-Release number of selected component (if applicable):
claws-mail-3.17.4-3.fc31.x86_64
gtk2-2.24.32-6.fc31.i686
glibc-2.30-8.fc31.x86_64

How reproducible:
100%

Steps to Reproduce:
1.run claws-mail on an i9-9900K system under fedora 31
2.watch it hang for 25 seconds on start
3.

Actual results:
Slow start

Expected results:
Speedy start

Additional info:
Some mailing list entries about this:
https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org/thread/6RZ4RWAZPHG7GKKYNQCQ3BZAXRMBLBSC/
https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org/thread/ROFGNTIOLGCRMIGY4MGKHF3ULVNTXE74/

Comment 1 Tom Horsley 2019-12-08 23:53:31 UTC

In case it is relevant, the AT_HWCAP from the AUX vector is bfebfbff on the i9-9900K.
In the virtual machine emulating IvyBridge it is 78bfbff

AT_HWCAP2 is 0x0 on both.

Comment 2 Tom Horsley 2019-12-09 12:44:18 UTC

As long as I'm chasing the HWCAP goose, I'll add that my desktop at work has b7ebfbff as hwcap, and claws-mail has no delay there,
so if this is hwcap related, there is only one bit different: 0x08000000 (if only I knew what that bit meant).

Comment 3 Tom Horsley 2019-12-10 23:16:06 UTC

Experimenting some more, I found everything that depends on gtk2 and tried running some of the program. They don't all encounter this delay, but another one that does have a 25 second delay is kasumi.

Comment 4 Tom Horsley 2019-12-14 18:37:45 UTC

I've gotten various updates since I first noticed this, and one of them seems to have fixed it.
I no longer see the long startup delays in the apps which previously had problems. I guess I'll close the bug.