Re: win32: disable shared LDAP cache by default
whoops, http://svn.apache.org/viewvc?view=revision&revision=1824811 On Tue, Feb 20, 2018 at 5:42 PM, William A Rowe Jr wrote: > Which patch? I think you are missing a digit. > > On Mon, Feb 19, 2018 at 5:57 PM, Eric Covener wrote: >> I am hoping this is fixed by >> http://svn.apache.org/viewvc?view=revision&revision=182481 which I >> stumbled onto from another direction. >> >> On Thu, Aug 3, 2017 at 5:58 AM, Stefan Sperling wrote: >>> There are numerous reports of Apache HTTPD looping forever on Windows >>> unless the LDAPSharedCacheSize option is set to zero. >>> >>> See for instance: >>> https://svn.haxx.se/users/archive-2014-05/.shtml >>> https://subversion.open.collab.net/ds/viewMessage.do?dsMessageId=564176&dsForumId=3 >>> https://subversion.open.collab.net/ds/viewMessage.do?dsForumId=3&viewType=browseAll&dsMessageId=539507 >>> https://stackoverflow.com/questions/44542654/collabnet-subversion-server-reaching-cpu-100-because-of-httpd-exe-process >>> >>> I looked around for a while but don't know yet if a corresponding issue >>> in the HTTPD bug tracker exists. Does anyone know? >>> >>> On the surface it looks like a memory pool corruption bug to me. >>> The stack trace posted in >>> https://svn.haxx.se/users/archive-2014-05/.shtml >>> points towards an endless loop in apr_pool_cleanup_kill(). >>> The trace ends at APR-util's >>> misc/apr_reslist.c:apr_reslist_cleanup_order_set, >>> and of the functions this calls only apr_pool_cleanup_kill() contains loops. >>> >>> I could not do any further debugging since I only had a production setup >>> to look at, which is stable with the workaround 'LDAPSharedCacheSize 0'. >>> I also do not have a Windows dev environment and I don't plan on digging >>> any further. >>> >>> Until the real bug gets found and fixed, I would recommend making the >>> known workaround the default on Windows. Because the winnt MPM runs a >>> single process, there is no benefit to a shared memory cache anyway. >>> >>> Should I commit this patch? >>> >>> Index: modules/ldap/util_ldap.c >>> === >>> --- modules/ldap/util_ldap.c(revision 1803972) >>> +++ modules/ldap/util_ldap.c(working copy) >>> @@ -2815,7 +2815,17 @@ static void *util_ldap_create_config(apr_pool_t *p >>> apr_thread_mutex_create(&st->mutex, APR_THREAD_MUTEX_DEFAULT, >>> st->pool); >>> #endif >>> >>> +#ifdef WIN32 >>> +/* XXX The shared memory cache can cause an endless loop on Windows. >>> + * See https://svn.haxx.se/users/archive-2014-05/.shtml and >>> + * similar reports elsewhere which recommend 'LDAPSharedCacheSize 0' >>> + * as a workaround. >>> + * Because the winnt MPM uses a single process a shared cache is >>> + * not needed anyway so leave it disabled by default. */ >>> +st->cache_bytes = 0; >>> +#else >>> st->cache_bytes = 50; >>> +#endif >>> st->search_cache_ttl = 6; >>> st->search_cache_size = 1024; >>> st->compare_cache_ttl = 6; >> >> >> >> -- >> Eric Covener >> cove...@gmail.com -- Eric Covener cove...@gmail.com
Re: win32: disable shared LDAP cache by default
Which patch? I think you are missing a digit. On Mon, Feb 19, 2018 at 5:57 PM, Eric Covener wrote: > I am hoping this is fixed by > http://svn.apache.org/viewvc?view=revision&revision=182481 which I > stumbled onto from another direction. > > On Thu, Aug 3, 2017 at 5:58 AM, Stefan Sperling wrote: >> There are numerous reports of Apache HTTPD looping forever on Windows >> unless the LDAPSharedCacheSize option is set to zero. >> >> See for instance: >> https://svn.haxx.se/users/archive-2014-05/.shtml >> https://subversion.open.collab.net/ds/viewMessage.do?dsMessageId=564176&dsForumId=3 >> https://subversion.open.collab.net/ds/viewMessage.do?dsForumId=3&viewType=browseAll&dsMessageId=539507 >> https://stackoverflow.com/questions/44542654/collabnet-subversion-server-reaching-cpu-100-because-of-httpd-exe-process >> >> I looked around for a while but don't know yet if a corresponding issue >> in the HTTPD bug tracker exists. Does anyone know? >> >> On the surface it looks like a memory pool corruption bug to me. >> The stack trace posted in >> https://svn.haxx.se/users/archive-2014-05/.shtml >> points towards an endless loop in apr_pool_cleanup_kill(). >> The trace ends at APR-util's >> misc/apr_reslist.c:apr_reslist_cleanup_order_set, >> and of the functions this calls only apr_pool_cleanup_kill() contains loops. >> >> I could not do any further debugging since I only had a production setup >> to look at, which is stable with the workaround 'LDAPSharedCacheSize 0'. >> I also do not have a Windows dev environment and I don't plan on digging >> any further. >> >> Until the real bug gets found and fixed, I would recommend making the >> known workaround the default on Windows. Because the winnt MPM runs a >> single process, there is no benefit to a shared memory cache anyway. >> >> Should I commit this patch? >> >> Index: modules/ldap/util_ldap.c >> === >> --- modules/ldap/util_ldap.c(revision 1803972) >> +++ modules/ldap/util_ldap.c(working copy) >> @@ -2815,7 +2815,17 @@ static void *util_ldap_create_config(apr_pool_t *p >> apr_thread_mutex_create(&st->mutex, APR_THREAD_MUTEX_DEFAULT, st->pool); >> #endif >> >> +#ifdef WIN32 >> +/* XXX The shared memory cache can cause an endless loop on Windows. >> + * See https://svn.haxx.se/users/archive-2014-05/.shtml and >> + * similar reports elsewhere which recommend 'LDAPSharedCacheSize 0' >> + * as a workaround. >> + * Because the winnt MPM uses a single process a shared cache is >> + * not needed anyway so leave it disabled by default. */ >> +st->cache_bytes = 0; >> +#else >> st->cache_bytes = 50; >> +#endif >> st->search_cache_ttl = 6; >> st->search_cache_size = 1024; >> st->compare_cache_ttl = 6; > > > > -- > Eric Covener > cove...@gmail.com
Re: win32: disable shared LDAP cache by default
I am hoping this is fixed by http://svn.apache.org/viewvc?view=revision&revision=182481 which I stumbled onto from another direction. On Thu, Aug 3, 2017 at 5:58 AM, Stefan Sperling wrote: > There are numerous reports of Apache HTTPD looping forever on Windows > unless the LDAPSharedCacheSize option is set to zero. > > See for instance: > https://svn.haxx.se/users/archive-2014-05/.shtml > https://subversion.open.collab.net/ds/viewMessage.do?dsMessageId=564176&dsForumId=3 > https://subversion.open.collab.net/ds/viewMessage.do?dsForumId=3&viewType=browseAll&dsMessageId=539507 > https://stackoverflow.com/questions/44542654/collabnet-subversion-server-reaching-cpu-100-because-of-httpd-exe-process > > I looked around for a while but don't know yet if a corresponding issue > in the HTTPD bug tracker exists. Does anyone know? > > On the surface it looks like a memory pool corruption bug to me. > The stack trace posted in https://svn.haxx.se/users/archive-2014-05/.shtml > points towards an endless loop in apr_pool_cleanup_kill(). > The trace ends at APR-util's misc/apr_reslist.c:apr_reslist_cleanup_order_set, > and of the functions this calls only apr_pool_cleanup_kill() contains loops. > > I could not do any further debugging since I only had a production setup > to look at, which is stable with the workaround 'LDAPSharedCacheSize 0'. > I also do not have a Windows dev environment and I don't plan on digging > any further. > > Until the real bug gets found and fixed, I would recommend making the > known workaround the default on Windows. Because the winnt MPM runs a > single process, there is no benefit to a shared memory cache anyway. > > Should I commit this patch? > > Index: modules/ldap/util_ldap.c > === > --- modules/ldap/util_ldap.c(revision 1803972) > +++ modules/ldap/util_ldap.c(working copy) > @@ -2815,7 +2815,17 @@ static void *util_ldap_create_config(apr_pool_t *p > apr_thread_mutex_create(&st->mutex, APR_THREAD_MUTEX_DEFAULT, st->pool); > #endif > > +#ifdef WIN32 > +/* XXX The shared memory cache can cause an endless loop on Windows. > + * See https://svn.haxx.se/users/archive-2014-05/.shtml and > + * similar reports elsewhere which recommend 'LDAPSharedCacheSize 0' > + * as a workaround. > + * Because the winnt MPM uses a single process a shared cache is > + * not needed anyway so leave it disabled by default. */ > +st->cache_bytes = 0; > +#else > st->cache_bytes = 50; > +#endif > st->search_cache_ttl = 6; > st->search_cache_size = 1024; > st->compare_cache_ttl = 6; -- Eric Covener cove...@gmail.com
