Login page blank with APC enabled

[optrex]

I have APC enabled with the below settings. Everything seems to work ok, with the excpetion of the login/login page which comes up blank or displays a 500 error depending on the browser. I am using APC 3.1.9 and php 5.3.3. If I turn off APC it works correctly but the site becomes considerably slower. There are no error logs in the XF admin area

Is there a problem with my settings or is there a way I can filter login/login to exclude it from being cached in APC. If so how do I do that?

apc.cache_by_default 1
apc.canonicalize 1
apc.coredump_unmap 0
apc.enable_cli 0
apc.enabled 1
apc.file_md5 0
apc.file_update_protection 2
apc.filters
apc.gc_ttl 60
apc.include_once_override 1
apc.lazy_classes 0
apc.lazy_functions 0
apc.max_file_size 2M
apc.mmap_file_mask /dev/zero
apc.num_files_hint 1000
apc.preload_path
apc.report_autofilter 0
apc.rfc1867 0
apc.rfc1867_freq 0
apc.rfc1867_name APC_UPLOAD_PROGRESS
apc.rfc1867_prefix upload_
apc.rfc1867_ttl 3600
apc.serializer default
apc.shm_segments experiment
apc.shm_size 100
apc.slam_defense 50
apc.stat 1
apc.stat_ctime 0
apc.ttl 60
apc.use_request_time 1
apc.user_entries_hint 20
apc.user_ttl 180
apc.write_lock 1

 

[Jake Bunce]

A 500 error is very generic. Is it recorded in the server logs? Ideally your logs will have more information about the error.

I don't know of any way to exclude that specific location.

 

[optrex]

there is nothing specific that I can see that relates to the issue

[Fri Mar 30 17:05:06 2012] [notice] caught SIGTERM, shutting down
[Fri Mar 30 17:05:08 2012] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Fri Mar 30 17:05:08 2012] [warn] RSA server certificate CommonName (CN) `Parallels Panel' does NOT match server name!?
[Fri Mar 30 17:05:08 2012] [warn] RSA server certificate CommonName (CN) `Parallels Panel' does NOT match server name!?
[Fri Mar 30 17:05:08 2012] [warn] RSA server certificate CommonName (CN) `Parallels Panel' does NOT match server name!?
[Fri Mar 30 17:05:08 2012] [warn] Init: Name-based SSL virtual hosts only work for clients with TLS server name indication support (RFC 4366)
[Fri Mar 30 17:05:08 2012] [notice] Digest: generating secret for digest authentication ...
[Fri Mar 30 17:05:08 2012] [notice] Digest: done
[Fri Mar 30 17:05:08 2012] [notice] mod_bw : Memory Allocated 0 bytes (each conf takes 32 bytes)
[Fri Mar 30 17:05:08 2012] [notice] mod_bw : Version 0.8 - Initialized [0 Confs]
PHP Warning: Directive 'safe_mode' is deprecated in PHP 5.3 and greater in Unknown on line 0
[Fri Mar 30 17:05:08 2012] [error] python_init: Python version mismatch, expected '2.6.5', found '2.6.6'.
[Fri Mar 30 17:05:08 2012] [error] python_init: Python executable found '/usr/bin/python'.
[Fri Mar 30 17:05:08 2012] [error] python_init: Python path being used '/usr/lib64/python26.zip:/usr/lib64/python2.6/:/usr/lib64/python2.6/plat-linux2:/usr/lib64/python2.6/lib-tk:/usr/lib64/python2.6/lib-old:/usr/lib64/python2.6/lib-dynload'.
[Fri Mar 30 17:05:08 2012] [notice] mod_python: Creating 4 session mutexes based on 10 max processes and 0 max threads.
[Fri Mar 30 17:05:08 2012] [notice] mod_python: using mutex_directory /tmp
[Fri Mar 30 17:05:08 2012] [warn] RSA server certificate CommonName (CN) `Parallels Panel' does NOT match server name!?
[Fri Mar 30 17:05:08 2012] [warn] RSA server certificate CommonName (CN) `Parallels Panel' does NOT match server name!?
[Fri Mar 30 17:05:08 2012] [warn] RSA server certificate CommonName (CN) `Parallels Panel' does NOT match server name!?
[Fri Mar 30 17:05:08 2012] [warn] Init: Name-based SSL virtual hosts only work for clients with TLS server name indication support (RFC 4366)
[Fri Mar 30 17:05:08 2012] [notice] Apache/2.2.15 (Unix) DAV/2 mod_fcgid/2.3.6 mod_python/3.3.1 Python/2.6.6 mod_ssl/2.2.15 OpenSSL/1.0.0-fips mod_perl/2.0.4 Perl/v5.10.1 configured -- resuming normal operations

 

[optrex]

I'm sure there are others using APC 3.1.9. What are your configs and has anyone else come across this problem?