Jeff F. will certainly have better critique, but it appears that the key structure and hash-algorithm aren't very well suited to each other.
You have 883,026 records in 3,000,017 groups, and one of the groups has 7,417 records in it, so you have at least 2,124,407 empty groups. I believe every disk sold in the last 5 or more years reads at least 4 frames at a time, so a separation of 4 (or 8, etc.) will likely improve speed as well. The fact that you have over 8% of 883,026 records hashing to the same group looks like the primary problem. The usual hash algorithms tend to give the best spread of records when the last several bytes of the key have the widest range of values. How are the 64 byte keys composed? Kind Regards, Richard Lewis --- On Tue 10/16, roy < [EMAIL PROTECTED] > wrote: File name = SALES-HIST-BR1 File type = 18 Number of groups in file (modulo) = 3000017 Separation = 1 Number of records = 883026 Maximum number of records in a group = 7417 Average number of bytes per record = 170.6213 Minimum number of bytes in a record = 64 Maximum number of bytes in a record = 2644 _______________________________________________ No banners. No pop-ups. No kidding. Make My Way your home on the Web - http://www.myway.com ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
