[ZODB-Dev] Re: [ZEO] Storage error with big transactions.

[Tres Seaver]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Jim Fulton wrote:
> On Feb 12, 2007, at 12:25 PM, Andreas Jung wrote:
> 
>> I have the following script to emulate a long running writing ZEO  
>> client
>> by writing 100MB to a page template:
>>
>> import transaction
>>
>> pt = app.foo
>> while 1:
>>    data = '*'*100000000
>>    T = transaction.begin()
>>    pt.pt_edit(data, 'text/html')
>>    T.commit()
>>    print 'done'
>>
>> This script fails badly during during the first commit() call. Is  
>> this a bug
>> or feature? I am using Zope 2.10.2 on MacOSX Intel.
> 
> Based on the traceback you gave, this looks like a bug.  I've  
> noticed, however, that large database records can lead to memory  
> errors at sizes much smaller than I would expect.  If the problem is  
> ultimately traced to a hidden memory error, there's not much that can  
> be done.  In the long run, I expect we'll advise that "large" objects  
> be put in blobs, where "large" might be smaller than one might  
> expect.  For example, I've seen 90MB records lead to memory errors  
> even on machines with a hundreds of megabytes free.

That sounds like a fragmented heap.


Tres.
- --
===================================================================
Tres Seaver          +1 540-429-0999          tseaver at palladion.com
Palladion Software   "Excellence by Design"    http://palladion.com
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2.2 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFF0f0I+gerLs4ltQ4RArFgAKCB0dTHcLLgoZ1ZAAq6XKbCaizAZgCfRFgT
iuCdpw99+dU/cwExlTPdTJ4=
=coHy
-----END PGP SIGNATURE-----