Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!columbia!rutgers!mit-eddie!genrad!decvax!ucbvax!cbatt!neoucom!wtm From: wtm@neoucom.UUCP (Bill Mayhew) Newsgroups: comp.sys.ibm.pc Subject: Re: Disk caching programs Message-ID: <360@neoucom.UUCP> Date: Wed, 14-Jan-87 11:02:27 EST Article-I.D.: neoucom.360 Posted: Wed Jan 14 11:02:27 1987 Date-Received: Thu, 15-Jan-87 01:09:37 EST References: <832@mprvaxa.UUCP> Organization: Northeastern Ohio Universities College of Medicine Lines: 28 Summary: Lightning not too great! I borrowed a copy of "lightning" from a friend to try out on my AT-compatible Epson Equity III. I set it up with a 128K buffer size for the cache. I found that in everyday use, the improvement in percieved performace was minimal, if any. For example, without lighting running, I ran DISKTIME.COM and came up with a throughput rate of 122,000 bytes/second on the fixed disk. With lightning, using a 128K cache, the throughput dropped to 92,000 bytes/second. Thus for long xfers of data that are bigger than the area that you reserve for the cache, you actually get a substantial decrease in performace. Lightning would be relatively useful for a database program that did lots of transfers of data in and out of files that were small enough to reside in the cache buffer. They include a demo file that illustrates this point nicely. Lightning would also be a welcome addition if you are not lucky enough to have a fixed disk on your system, as it does improved the percieved performance on floppies quite a bit. Oh yes, I didn't think lightning was enough of a value to warrant its purchase in my case, so I used Norton's wipefile to avoid being a pirate (for any of you sensitive readers out there). --Bill