FB 1.5.1.4481

I have a routine which does:

Select single record by PK from single table.
Issue a new update on same record to same table.

This happens in a transaction and is repeated for each record. Normally a
couple dozen times. The complete set is done in a trasnaction, not each one.

Because of a flaw we had a situation that instead of a a few dozen times it
ran 10,000. Now we fixed this, but the bigger problem is FB just dies. It
appears that when a transaction log is too big it just dies?? We've
reproduced this on our test server and two developer machines.

The erros are below. When I look in Guardian, it says server terminated
abnormally or something like that.

Sometimes we get this:
Exception Details: FirebirdSql.Data.Firebird.FbException: I/O error during
"CreateFile (open)" operation for file
"D:\IISDomains\purchase.atozed.com\Data\APPRinok.gdb" Error while trying to
open file

But normally we get this:
Error reading data from the connection.
Description: An unhandled exception occurred during the execution of the
current web request. Please review the stack trace for more information
about the error and where it originated in the code.

Exception Details: FirebirdSql.Data.Firebird.FbException: Error reading data
from the connection.

Source Error:

An unhandled exception was generated during the execution of the current web
request. Information regarding the origin and location of the exception can
be identified using the exception stack trace below.

Stack Trace:

[FbException: Error reading data from the connection.
]
FirebirdSql.Data.Firebird.FbTransaction.Rollback() +121
ADOPlus.DBConnection.RollbackTrans() +13