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<P><FONT SIZE=2 FACE="Arial">We have a recurring problem, not an urgent one, that I'd like to see if anyone has Wise Ideas about.</FONT>
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<P><FONT SIZE=2 FACE="Arial">We have an environment running under HP-Ux 10.2, Powerhouse 7.33.D3, C-ISAM (unsure of version, but it's the latest version that 7.33.D3 came with) and FORTRAN (ick!).</FONT></P>
<P><FONT SIZE=2 FACE="Arial">We have an Image/3000 emulator built by a contractor: it takes the Image calls and translates them into C-ISAM calls - we've had this since 1994 and it has been very reliable.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">This particular application has one large data file (2 million plus rows) which is heavily indexed: data file currently is about 650 K but the index is twice that size.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">We have a FORTRAN program that does batch updates to the data file, locking mode 1, around the entire transaction. This program<U> only</U> adds to the data file.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">We also have Powerhouse screens that allow users to do maintenance on the data file, which often means deleting records that were uploaded erroneously.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">The Powehouse screens use the default locking scheme … there is nothing explicitly written in the code or dictionary regarding locking.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Periodically we come up with corrupted indexes on the main data file and have to use the bcheck utility to re-build the indexes. Sometimes this happens several times in a couple of months, or like this week, it will be almost a YEAR between occurrences.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I had long thought that we must have the FORTRAN program and the maintenance screens tripping over each other. This past week, when the problem showed up I actually saw 2 users in the maintenance screens as well as one of the FORTRAN uploads taking place: one of the maintenance users actually received a message that the screen was waiting on locks. Then, the corrupted index showed up.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">The FORTRAN does lock, although it is a mode 1 lock, which allows other concurrent users. </FONT>
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<P><FONT SIZE=2 FACE="Arial">So, what I'm thinking is that our FORTRAN program's locks are not keeping the maintenance screens out, the maintenance screens are deleting entries (requireing notoriously slow index rebuilds in C-ISAM) and the two processes working against each other are resulting in messed-up indexes. Does this make sense?</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Thanks,</FONT>
<BR><FONT SIZE=2 FACE="Arial">Guy L. Werry</FONT>
<BR><FONT SIZE=2 FACE="Arial">Senior Systems Analyst</FONT>
<BR><FONT SIZE=2 FACE="Arial">Hudson Bay Mining & Smelting Co., Limited. </FONT>
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