On Jul 2, 2005, at 9:32 AM, Billy Newsom wrote:
If you aren't familiar with the Matt Simerson mysql patch, it was born because there can be major lookup problems with the cdb file, especially using POP before SMTP. Imagine the POP server populating the text file (and re-compiling the CDB) 10 times per second. Now, imagine 20 queries per second on the CDB file, that in some cases is in the middle of a file alteration. The disk, in cases like this, hardly ever gets to writing the file from a kernel buffer, so what you are seeing is memory accesses on this file most of the time. There will simply be cases where the CDB file gets hammered too hard and corrupted. It will need attention by the admin during peak hours.


If I recall the thread though, the server in question is NOT set up for POP before SMTP. So, the cdb file is static and does not get updated. If it has 5 or so entries for the servers that will feed it, I would have to agree that a cdb lookup would to a static file of 5 entries would be more efficient than a MySQL query (which has to be parsed by the MySQL server) for the same lookup.

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Tom Collins  -  [EMAIL PROTECTED]
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