[Zope-dev] still segfaults, this time no ZMySQLDA

Leonardo Rochael Almeida leo@hiper.com.br
26 Feb 2002 20:11:30 -0300


Hi, It's me and my instability problems again :-)

The system:
Zope-2.4.4b1 (binary linux-x86 from zope.org)
Python-2.1.2 (see above)

Products (excluding Zope defaults and ZClass based ones):
LocalFS=20
Pagina0_Base (Hiperl=F3gica product)
Pagina1_Base (Hiperl=F3gica product)
Renderable
exUserFolder

It has an 800+MiB Data.fs (when packed) that is crammed full of python
scripts. I'm still looking for a way to recompile them all without
sending the machine (1GiB physical RAM) into a swap storm which would
ultimately crash Zope or the machine and keep it from commiting the
transaction that caused all the trouble in the first place (one of these
days I'll refactor the subtransaction code out of the ZCatalog and into
a ZopeFind that will accept an action parameter, along with a
subtransaction one, to perform these kinds of global maintenance in a
reasonable way).

None of the products mentioned above use C compiled modules. I disabled
all the use of mysql on this instance so that I could remove ZMySQLDA
and faked the authentication system so that it's usage pattern remained
the same even without mysql. After that I reenabled the cycle-gc.

The system started crashing about every 5 minutes.

As much as I'd have liked pointing a finger at ZMySQLDA, start the
process of migration to PostgreSQL and consider this problem solved once
and for all, I have finally come to the conclusion that there is no one
else to blame but Zope and Python themselves. I have since reenabled
ZMySQLDA use by the site and disabled the cycle-gc.

The options I think I have left:
* Try the new ExtensionClass.h
* Run Zope under a memory analiser such as Valgrind (which might not be
feasible if the runtimes are too slow):
http://devel-home.kde.org/~sewardj/
* Try migrating to Zope-2.5.1b1

The situation is starting to look desperate. We now have to restart the
server twice a day to keep the machine from swapping. This can't go on
any longer. Any suggestion is apreciated.

--=20
Ideas don't stay in some minds very long because they don't like
solitary confinement.