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is more swap is harmful to system

By jpsarkar_2001 ·
it is recomanded that 2*ram or 3*ram is sufficient for swap. But if swap memory is kept more than that can anybody say will it be hamful to system performance?

suppose i hav 1GB RAM if i keep 3GB swap it is o.k . But if i keep more than 3GB swap will system be slow?

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is more swap is harmful to system

by TheChas In reply to is more swap is harmful t ...

By the benchmark test numbers, Windows runs the 'fastest' with a swap file of 2X RAM or less.

In the real world, a larger swap file can reduce system crashes, and is not that much slower.

I run 1 GB to 5 GB swap files on a seperate logical drive on my systems. Anytime the performance penalty is small, I choose stability over speed.

If you run high resolution graphics editing, large spread sheets, or CADD, the extra swap file space is very usefull.

Another cunundrom of the 2X RAM rule, is that the less RAM you have, the larger a swap file you realy need.
I am re-thinking my minimum swap file size. A realistic minimum may be the larger of 1GB total of RAM and Swap file, or 2X installed RAM.

The 2X rule is a holdover from Windows 3.11 where 2X RAM was all the swap file Windows would make use of.

If you are looking for numbers, I have not run any tests personaly.
From what I have read, the actual penalty of a 3GB swap file will be less than a 2% reduction in 'system' performance.

Chas

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is more swap is harmful to system

by jpsarkar_2001 In reply to is more swap is harmful t ...

The question was auto-closed by TechRepublic

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is more swap is harmful to system

by Thamer In reply to is more swap is harmful t ...

What is your operating system?

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is more swap is harmful to system

by Thamer In reply to is more swap is harmful t ...

Sorry ... I withdraw my question as I opend yours through the "view all open" feature.

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is more swap is harmful to system

by jpsarkar_2001 In reply to is more swap is harmful t ...

The question was auto-closed by TechRepublic

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is more swap is harmful to system

by cpfeiffe In reply to is more swap is harmful t ...

I see an answer posted in relevance to Windows, but I'm assuming you are running Unix as this is under the Unix forum. Different vendors in Unix have different opinions on swap that range from 1X to 2X RAM for most systems and up to 3X RAM for certain applications. It is also stated that the less RAM you have the more you want to lean towards the higher end of swap. The best general breakdown I saw of this was < 512 MB RAM should use 2.5X RAM for swap. 512 MB - 1 GB RAM should use 2X RAM for swap. 1 GB RAM - 2 GB RAM should use 1.5 RAM for swap. >2 GB RAM should use 1X RAM for swap. That being said, I've done several benchmarks and security related tests which led to more benchmarking of OS capabilities and found that it really doesn't make a difference for performance as long as you just don't run out. Because of the way Unix uses memory (RAM + swap) and the new "feature" in most Unix operating systems for memory reservations it is important to have more swap than RAM. 1.25XRAM should be enough. Don't ever use less than that. Anything additional isn't necessary and is just a waste of disk space in my opinion. Unix needs everything to run in true RAM so there is no point in having much more swap than RAM. The only catch is that many unix processes reserve more memory than they will need so this is why we make swap slightly bigger. If you have the disk space and want to use 2X or 3X or even 4X RAM to be safe it won't hurt your performance it will just waste disk space. Also note that on many unix systems a single swap file can only be 2 GB. Some even limit the swap file system but many don't any more. In Unix you can create multiple swap files and combine them to get the amount of swap you need. Using more than one swap file does slow performance. The best rule of thumb is to use one swap file system (tmpfs type) to be your full swap area. I hope this is helpful.

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is more swap is harmful to system

by jpsarkar_2001 In reply to is more swap is harmful t ...

The question was auto-closed by TechRepublic

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is more swap is harmful to system

by anitha430 In reply to is more swap is harmful t ...

It depends on the processor speed, How much memory is required at any time by the applications, which memory area you are switching/swapping, how often etc. If you go by the cache rules more cache/swap does slow down the system. Depending on all theabove cretirea a benchmark will do a lot good though mathematical formulas does exist to arrive at the optimum config.

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is more swap is harmful to system

by jpsarkar_2001 In reply to is more swap is harmful t ...

The question was auto-closed by TechRepublic

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is more swap is harmful to system

by jpsarkar_2001 In reply to is more swap is harmful t ...

This question was auto closed due to inactivity

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