[lxml-dev] ERESTARTNOHAND error

[Frédéric Mantegazza]

Hello,

Some months ago, I migrated some part of our code from libxml2/libxslt 
modules to lxml module (which is much pythonic!). But my code never worked, 
because of a seg. fault :o(

The crash occurs at:

    result = self.__xslFilter.apply(tree, {'filename':"'%s'" % baseName})

This code is used inside a Pyro server (Pyro is a client/server framework. 
see http://pyro.sourceforge.net), so in a multi-threaded environement.

I ran the server using strace to see what happens: I got a ERESTARTNOHAND 
error. This error is very strange, and Google does not give usefull 
informations...

I tested my code out of Pyro: it works. I made a simple Pyro serveur with 
just this part of the code: it works too. It only crashes when using the 
real server, which uses a lot of multi-threads calls.

Another guy had a similar problem, but the error was in the python mysql 
client wrapper, only on stressed usage.

It seems that there is a problem in either lxml and pymysql when used in a 
stressed multi-threaded way. I use locks in my server to avoid re-entrant 
calls to lxml, so I'm sure the problem is not there; I feel that it is 
related to the number of threads running...

Does anyone has an idea of that problem?

Thanks,

PS: I also use lxml from mod_python, and all is working fine.

-- 
   Frédéric