My laptop has 8GB RAM and have two hard disk, one is SSD 250 GB and other one is hdd and 500 GB i want to use the SSD drive as / partition and create swap partition in hdd, is this make any deference in performance of linux system, the second question is what size will be better for swap partition for good performance of the latest linux distributions.

Looks like a good idea. Shouldn't affect performance unless you have other problems (bad memory leak say). With lots of disk, make it any size you like - say 8G. No real reason, just a number till you know how if it ever gets used.

It is easy to run tests on your system to see what swap size and configuration works best for you. Set up the various swap partitions that you are considering. Then use the swapon and swapoff commands to switch among your various swap partitions. Run heavy tests of your typical workload against each configuration and see which configuration performs best. If you do this I ask you to post the results here on linuxquestions to let us know what works best for you.

see;

man swapon

man swapoff

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Steve Stites

P.S. One of your test runs should be with no swap partition enabled. That will give a base performance to measure how much each swap partition improves performance, if any.

Over the years I have found that the best performance improvement when using a two drive system is by placing /usr on a separate drive from the rest of the Linux system.

This should work just fine.

Back in the olden days, when hard drives were new and very small by today's standards (my first home computer in 1989 had an 85MB HDD), it was quite common to have different partitions on different physical drives. That's one reason /etc/fstab is configured the way it is.