Re: [Zope] Preventing Zope Spinning?

2006-05-30 Thread Chris Withers
Jens Vagelpohl wrote: Persistent caches can introduce odd errors, unfortunately. They can create inconsistencies between what a ZEO client thinks the database state is and what the ZEO server thinks. Not recommended for production setups. Don't necessarily agree with this. If the clients get

Re: [Zope] Preventing Zope Spinning?

2006-05-30 Thread Jens Vagelpohl
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 30 May 2006, at 15:26, Chris Withers wrote: Jens Vagelpohl wrote: Persistent caches can introduce odd errors, unfortunately. They can create inconsistencies between what a ZEO client thinks the database state is and what the ZEO server

Re: [Zope] Preventing Zope Spinning?

2006-05-30 Thread Chris Withers
Jens Vagelpohl wrote: There are several production setusp where I use persistent client caches and I've had very few problems with them... I'm sorry, this is not a matter of agreeing. It is a matter of personally observed facts. Yes, which is exactly what I'm providing ;-) I've seen big

Re: [Zope] Preventing Zope Spinning?

2006-05-26 Thread Dieter Maurer
Paul Winkler wrote at 2006-5-25 13:05 -0400: ... Large files really hurt ZEO performance, both reads (since they're likely not in the cache, and if they are, they evict lots of other useful stuff), and for writes. Files use 64 kB chunks -- thus the problem you describe occurs with files I would

Re: [Zope] Preventing Zope Spinning?

2006-05-25 Thread Jonathan
How about setting up persistent caches for your zeo clients, so that when the zeo server goes down you save some cache-reloading time when it restarts? Jonathan - Original Message - From: Brian Brinegar [EMAIL PROTECTED] To: zope@zope.org Cc: David S Carmichael [EMAIL PROTECTED];

Re: [Zope] Preventing Zope Spinning?

2006-05-25 Thread Jens Vagelpohl
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Persistent caches can introduce odd errors, unfortunately. They can create inconsistencies between what a ZEO client thinks the database state is and what the ZEO server thinks. Not recommended for production setups. jens On 25 May 2006, at

Re: [Zope] Preventing Zope Spinning?

2006-05-25 Thread Jonathan
Subject: Re: [Zope] Preventing Zope Spinning? -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Persistent caches can introduce odd errors, unfortunately. They can create inconsistencies between what a ZEO client thinks the database state is and what the ZEO server thinks. Not recommended

Re: [Zope] Preventing Zope Spinning?

2006-05-25 Thread Brian Brinegar
Jonathan, We have debated this, however the time necessary to revalidate the cache can be several minutes (maybe more) at startup for a 2 gig cache. If only one client was going down at a time this would not be a problem, however in the event that someone clicks reload until all of the clients

Re: [Zope] Preventing Zope Spinning?

2006-05-25 Thread Paul Winkler
On Thu, May 25, 2006 at 10:49:10AM -0400, Brian Brinegar wrote: The majority of the Purdue University Engineering web presence is provided via a cluster running ZEO. We offer hosting for every school, department, faculty, staff, and student in the College. Because of this we have a large

Re: [Zope] Preventing Zope Spinning?

2006-05-25 Thread Dieter Maurer
Brian Brinegar wrote at 2006-5-25 10:49 -0400: ... What I would like is some sort of timeout for requests This is very difficult: There is no safe way to abort a thread without its help -- an the thread might be in a condition where it does not recognize that its help is needed (e.g. it