Re: NT vs. Unix

On 14 Feb 1999 16:33:32 GMT, gjlinker_at_aol.com (Gjlinker) wrote:

>Environment:
>Compac server dual processor P200
>NT4 + Oracle 7.3 + 600 MB memory + 4 GB disk
>10 users selecting 100 rows from a 150.000 row table using indexes.
>15 VB programs connected via ODBC running on the server.
>
>Result:
>Processors busy for most of the time 75-100%
>Very slow performance due to high write times of Oracle.
>
>Analysis:
>Apparently PC hardware does not write to disk when processor is busy over 80%
>creating huge write times in Oracle.

  One thing I don't see mentioned... does the machine have a full-fledged Ultra-Wide SCSI disk drive, or is drive a cheap-o level-1 EIDE where the CPU has to babysit each byte being read or written from/to the drive? SCSI drives aren't mechanically faster, but they do have their own chips to handle scatter/gather, and do requested operations on their own. Ideally, the main CPU issues a read or write request, and a pointer to an area in memory, then disconnects. The SCSI carries out its orders and issues an interrupt to the main CPU when finished. In the meantime, the main CPU can be number-crunching. You may not see a difference in single- tasking DOS, but it's quite important in a true multi- tasking environment.

Walter Dnes <waltdnes_at_interlog.com> procmail spamfilter http://www.interlog.com/~waltdnes/spamdunk/spamdunk.htm Why a fiscal conservative opposes Toronto 2008 OWE-lympics http://www.interlog.com/~waltdnes/owe-lympics/owe-lympics.htm Received on Sun Feb 14 1999 - 19:18:59 CST