Hi, On Wednesday 20 August 2008 21:51:05 Kalle Sommer Nielsen wrote: > 2008/8/20 Arnaud Le Blanc <[EMAIL PROTECTED]>: > > Hi, > > > > On Tuesday 19 August 2008 18:22:44 Andi Gutmans wrote: > >> OK checked with Zeev. It seems there are some significant limitations at > >> least on Windows including that it doesn't work with LoadLibrary() > >> (which is our bread and butter). > > > > Ok, so there is the same limitations than on Linux with dlopen() :( > > > >> There may also be some size limitations on thread local storage. > >> In any case, this is Windows-only feedback and we may find additional > >> limitations/compatibility issues on other platforms. > >> > >> As there are clear benefits to an increased use of TLS (we already use > >> it for index caching today) I definitely suggest to revisit this issue > >> and try and figure out for the variety of platforms whether there's some > >> middle ground that we can make work. It sounds like a non-trivial > >> project though. > >> Arnaud, are you setup to also play around with Windows and possibly some > >> other OSes to look into this further? > > > > Yes, I will try at least with Windows (XP, so no IIS) and FreeBSD. > > > > Windows XP Professional have IIS, all you need is your CD and then > install it from the Add/Remove programs. It's IIS 5.1, which should be > good enough.
Thanks, I didn't known that. I did not have a Professional version of Windows but I will try to get one. > > >> > >> Andi > >> > >> > >> > -----Original Message----- > >> > From: Arnaud Le Blanc [mailto:[EMAIL PROTECTED] > >> > Sent: Monday, August 18, 2008 10:00 PM > >> > To: Andi Gutmans > >> > Cc: PHP Development > >> > Subject: Re: [PHP-DEV] [PATCH] ZTS as fast as non-ZTS > >> > > >> > Hi, > >> > > >> > Yes, I have looked for the issue with --with-tsrm-full-__thread-tls > >> and there > >> > are effectively some issues. > >> > > >> > When building PIC code, the used TLS model is a static model which > >> does not > >> > allow modules to be loaded at run-time. glibc's dlopen() sometimes > >> allow such > >> > code to be loaded at runtime when it finds some free memory, that's > >> why -- > >> > with- > >> > tsrm-__thread-tls works, but it is not expected to always work. > >> > > >> > So when building PIC code that's expected to work only when the > >> > server/application links the PHP module, or when using LD_PRELOAD, > >> etc. > >> > > >> > Building non-PIC code allows to use a dynamic TLS model, which allows > >> to load > >> > modules a run-time, but it is less efficient (4.8s in bench.php, still > >> faster > >> > than unpatched version, even non-PIC, but less efficient). > >> > > >> > Regards, > >> > > >> > Arnaud > >> > > >> > On Tuesday 19 August 2008 06:18:51 Andi Gutmans wrote: > >> > > Hi Arnaud, > >> > > > >> > > I remember that at the time we looked at thread local storage and > >> there > >> > > were some real issues with it. I can't remember what as it was about > >> 7+ > >> > > years ago. > >> > > I will ask Zeev if he remembers and if not search my archives (don't > >> > > have years prior to 2007 indexed :'( ). > >> > > > >> > > Andi > >> > > > >> > > > >> > > > >> > > > >> > > > -----Original Message----- > >> > > > From: Arnaud Le Blanc [mailto:[EMAIL PROTECTED] > >> > > > Sent: Saturday, August 16, 2008 7:19 PM > >> > > > To: PHP Development > >> > > > Subject: [PHP-DEV] [PATCH] ZTS as fast as non-ZTS > >> > > > > >> > > > Hi, > >> > > > > >> > > > Currently the way globals work forces to pass a > >> thread-local-storage > >> > > pointer > >> > > > across function calls, which involves some overhead. Also, not all > >> > > functions > >> > > > get the pointer as argument and need to use TSRMLS_FETCH(), which > >> is > >> > > slow. For > >> > > > instance emalloc() involves a TSRMLS_FETCH(). An other overhead is > >> > > accessing > >> > > > globals, using multiple pointers in different locations. > >> > > > > >> > > > The following patch caches each global address in a native TLS > >> > > variable so > >> > > > that accessing a global is as simple as global_name->member. This > >> > > removes the > >> > > > requirement of passing the tls pointer across function calls, so > >> that > >> > > the two > >> > > > major overheads of ZTS builds are avoided. > >> > > > > >> > > > Globals can optionally be declared statically, which speeds up > >> things > >> > > a bit. > >> > > > > >> > > > Results in bench.php: > >> > > > non-ZTS: 3.7s > >> > > > ZTS unpatched: 5.2s > >> > > > ZTS patched: 4.0s > >> > > > ZTS patched and static globals: 3.8s > >> > > > > >> > > > The patch introduces two new macros: TSRMG_D() (declare) and > >> > > TSRMG_DH() > >> > > > (declare, for headers) to declare globals, instead of the current > >> > > "ts_rsrc_id > >> > > > foo_global_id". These macros declare the global id, plus the > >> __thread > >> > > pointer > >> > > > to the global storage. > >> > > > > >> > > > ts_allocate_id now takes one more callback function as argument to > >> > > bind the > >> > > > global pointer to its storage. This callback is declared in > >> > > TSRMG_D[H](). > >> > > > > >> > > > As all TSRMLS_* macros now does nothing, it is needed to call > >> > > ts_resource(0) > >> > > > explicitly at least one time in each thread to initialize its > >> storage. > >> > > A new > >> > > > TSRMLS_INIT() macro as been added for this purpose. > >> > > > > >> > > > All this is disabled by default. --with-tsrm-__thread-tls enables > >> the > >> > > features > >> > > > of the patch, and --with-tsrm-full-__thread-tls enables static > >> > > declaration of > >> > > > globals. > >> > > > > >> > > > It as been tested on Linux compiled with --disable-all in CLI and > >> a > >> > > bit in > >> > > > Apache2 with the worker MPM. Known issues: > >> > > > - Declaring globals statically (--with-tsrm-full-__thread-tls) > >> causes > >> > > troubles > >> > > > to dlopen(), actually Apache wont load the module at runtime (it > >> works > >> > > with > >> > > > just --with-tsrm-__thread-tls). > >> > > > - The patch assumes that all resources are ts_allocate_id()'ed > >> before > >> > > any > >> > > > other thread calls ts_allocate_id or ts_resource_ex(), which is > >> > > possibly not > >> > > > the case. > >> > > > > >> > > > The patch needs some tweaks and does not pretend to be included in > >> any > >> > > branch, > >> > > > but I would like to have some comments on it. > >> > > > > >> > > > The patch: http://arnaud.lb.s3.amazonaws.com/__thread-tls.patch > >> > > > > >> > > > Regards, > >> > > > > >> > > > Arnaud > >> > > > > >> > > > > >> > > > -- > >> > > > PHP Internals - PHP Runtime Development Mailing List > >> > > > To unsubscribe, visit: http://www.php.net/unsub.php > >> > > > >> > > > >> > >> > > > > Regards, > > > > Arnaud > > > > -- > > PHP Internals - PHP Runtime Development Mailing List > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > > > > > -- > Kalle Sommer Nielsen > Regards, Arnaud -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
