Messages in this thread | | | Date | Wed, 06 Jun 2001 10:14:18 -0700 | From | Ben Greear <> | Subject | Re: Break 2.4 VM in five easy steps |
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Richard Gooch wrote: > > Daniel Phillips writes: > > On Wednesday 06 June 2001 10:54, Sean Hunter wrote: > > > > > > Did you try to put twice as much swap as you have RAM ? (e.g. add a > > > > 512M swapfile to your box) > > > > This is what Linus recommended for 2.4 (swap = 2 * RAM), saying > > > > that anything less won't do any good: 2.4 overallocates swap even > > > > if it doesn't use it all. So in your case you just have enough swap > > > > to map your RAM, and nothing to really swap your apps. > > > > > > For large memory boxes, this is ridiculous. Should I have 8GB of > > > swap? > > Sure. It's cheap. If you don't mind slumming it, go and buy a 20 GB > IDE drive for US$65. I know RAM has gotten a lot cheaper lately (US$66 > for a 512 MiB PC133 DIMM), but it's still far more expensive. If you > can afford 4 GiB of RAM, you can definately afford 8 GiB of swap.
For me, the problem is not the money. If I have a system that needs 4GB of RAM, it is highly unlikely that I would ever want to be running this machine with 8GB of swap active. However, I may be willing to tollerate 1GB of swapping before paging to disk slowed things down too much. This is the exact scenario I had when dealing with a large Sun machine running Oracle & some other stuff. Oracle is dedicated large amounts of RAM, but if I wanted to run a quick, memory intensive program too, (and at the moment performance isn't all that big of a deal), then using some swap is OK.
So, I too cast my vote for the 2*RAM requiment to be odious and in need of fixing!! It could be a suggestion, but I would consider that if not following the suggestion caused more than 10% slowdown, then things are still broken, and optimally, it should work like the 2.2 does (in other words, I don't notice, and don't particularly care how much swap per RAM I need, just how much total RAM-like-stuff I need.)
Thanks, Ben
-- Ben Greear <greearb@candelatech.com> <Ben_Greear@excite.com> President of Candela Technologies Inc http://www.candelatech.com ScryMUD: http://scry.wanfear.com http://scry.wanfear.com/~greear - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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