Posted by jim guerber (66.180.141.237) on September 24, 2003 at 16:56:38:
In Reply to: Error 8E posted by Kimberleigh Olague on Wed, 24 Sep 2003 14:25:30 :
Kim,
This is one of those things that I want to explain on this forum so that everyone can understand what the problem may be. Error 8E comes from only one place in comet. This has to do with type N directories. In type N directories, there is no centralized file system that could take care of multiple users accessing a file simultaneously. Comet uses record locking to provide this capability.
On ANY file access, since a node may be modifying underlying data structures, Comet must gain exclusive access to the file for a very short period of time, (on the order of a few milliseconds).
Our file server products take care of this internally by providing appropriate queuing behind each file. Type N directories have no such Que. When a node wants exclusive access, it locks byte 1 of the file. If the lock fails (some other node already has byte 1 locked), this node will wait and try again after 5 clock ticks (about 1/4 second). It will try 800 times to lock the byte before giving up.
This mechanism works fine for small number of nodes WITH SIMILAR SPEED COMPUTERS. When the mix of computers increases, the time it takes for the windows file system to transmit the lock call to the server becomes significant. Faster computers will successfully gain access to the file to the detriment of slower computers. This is especially bad if some nodes have a 100mb network connection to the server while others have only 10mb.
This is the best explanation I can come up with for those 8E errors. Sorry if the customer must pay more money for the installation, but the reason is caused by the customer simply OUTGROWING this scheme.
Comet 2004 will not support type N directories. Customers that want to share files MUST use CometServe32 or CometServeNLM.
: Hello,
:
:I have installed all the latest Comet programs to one of my customers
:UTL, REL, CED, UTR, and COSW C2K3325. (I know that last one is not the =
:latest)
:They seem to be getting a lot of 8E errors, timing out running certain =
:programs.
:Any ideas?
:
:Thanks,
:Kim
:
:
:Kimberleigh A. Olague
:LTC, Inc.
:(510) 657-6673 (510) 657-6704 Fax
:Support@ltc-software.com
: