Prevent Server Termination of c-treeACE from Data and/or Index LRU Cache Miss Limitations

When a c-treeACE Server is running with the configuration options DATA_LRU_LISTS or INDEX_LRU_LISTS set greater than 1, after a large number (2^32, over 2 billion) data or index cache misses occur, the c-tree Server terminates with an unhandled exception. These options default to 4 in c-treeACE Version 9. Thus all c-treeACE Version 9 servers are susceptible to this situation. You can verify these options in the server startup information found in the server status log file, CTSTATUS.FCS.

When a cache page is required to hold a page that is not already in cache and multiple data or index LRU lists are in use, the data and index cache logic increments a variable used to calculate which data or index LRU list is to be used . However, the variable was declared as a signed long integer, and after 2^32 increments, became negative, resulting in a negative index offset for an array of data/index cache LRU list mutexes. Redeclaring the variables as unsigned long integers resolves this issue.