How much power does Linux need?

[Bruce Jin]

I installed Mandrake 8.0 on a P5-120 box with 16 Mb RAM (win95 was removed). It is very slow. Do I need more RAM or this box is simply to old?
Thanks.
Bruce

[Frank Carver]

Depends a bit what you are doing with the machine.
16MB is probably low these days (you can tell this if the disk seems to "thrash" when you do things), especially if you are using a big, colourful GUI. A machine with that spec should be nippy enough when using the command line though.
Can you tell us a bit more about what you want/need to do with this machine ?

[Bruce Jin]

Thanks Frank.
I want use this Linux as a servlet server. I need to install JDK 1.3 JRE and Tomcat on it. I don’t know if the RAM is the only problem. The box is a P5-120.
Thanks.

[Michael Ernest]

The RAM will be a problem with Tomcat.
Here's a site I found that benchmarks several machines of this approximate caliber. I mention it here so you can see for yourself the differences a change in CPU, memory complement, and disk type might make. Notice that the most dramatic improvements come from adding a SCSI disk -- that's because memory paging becomes far less of a ball-and-chain on system I/O. Excessive swapping (thrashing) on a cheap-o EIDE/IDE drive is what usually drags an otherwise useful low-end box to its knees.
If money is an issue, use these tables to determine the biggest likely bang for your buck. Memory's way cheap right now, disks aren't far behind, and 200 MHz CPU's probably cost as much to ship as buy. ;-). Quadrupling memory would be good for starters, but a faster disk subsystem means you'll thrash much more efficiently.
[ January 22, 2002: Message edited by: Michael Ernest ]

[Frank Carver]

I'd agree. The RAM is the main issue. I've had great performance out of low-spec processors (P-133, K6-233 Ppro-200 etc.) but without at least (say) 48MB of RAM you will hit real problems running any decent sized server-side Java applications.
Up until a few weeks ago my main servlet/JSP test server was an old P233 with 64MB of RAM running Java 1.3 and Resin 2.0.4, and that was easily powerful enough to compile up JSPs, process complex XSLT on-the-fly and still give snappy performance.
What sort of RAM chips does your machine take? (I'd guess at EDO simms) and how many RAM slots do you have?. I may be able to point you to a good source of supply, or even "do a deal" on some from my own stock.

[Bruce Jin]

Thank you for the info.
The box is Gateway. So I think it will take 72-pin SIMM (EDO). It has 4 memory slots. 2 of them are taken. I guest this machine can take memory chips in pairs only. If you can point to me to a good source of supply, or even "do a deal" on some from your own stock that would be great.

[Frank Carver]

The ones I have spare probably aren't big enough ( and would cost too much to ship over to the USA), but I've just had a look at eBay and it looks like you can get a pair of 32MB EDO simms for typically $20-$25, or a pair of 64MB for about $50. Check it out:

<a href="http://search.ebay.com/search/search.dll?MfcISAPICommand=GetResult&ht=1&SortProperty=MetaEndSort&query=EDO</a rel="nofollow">" target="_blank">http://search.ebay.com/search/search.dll?MfcISAPICommand=GetResult&ht=1&SortProperty=MetaEndSort&query=EDO[/URL]
or on Yahoo Auctions at:
<a href="http://search.auctions.shopping.yahoo.com/search/auc?p=EDO&st=auct&alocale=0us&acc=us</a rel="nofollow">" target="_blank">http://search.auctions.shopping.yahoo.com/search/auc?p=EDO&st=auct&alocale=0us&acc=us[/URL]
Just make sure you don't buy ECC RAM unless you actually need it (doubtful)
If anyone hasn't already registered for eBay (it's free!), then please feel free to click here to get me a small referral kickback Thanks.
[ January 24, 2002: Message edited by: Frank Carver ]

[Bruce Jin]

Thanks Frank!
Thanks Michael for the Linux benchmark link!

[Tim Holloway]

Just as a ballpark figure from experience - older versions of Linux would run in about 4-16 MB of RAM, but to run X-windows you really needed 16MB or more.
Java's another matter. It's a pig. I run Tomcat on an old P-200 with about 90MB of RAM, but you can grow impatient waiting for JSPs to compile. On the other hand the box was free, and nobody's paying me for a high-performance server...