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Interestingly I always use swapfiles and this page made me realise there can be a performance impact if the filesystem is old - the lkml link says as long as the swap file isn't fragmented there's no impact

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In practice, there’s a potentially tremendous impact if you’re using a spinning metal disk. Sectors at the beginning of the disk (which is at the outer edge) are read/written way faster than sectors at the end. File systems tend to prefer writing files at the beginning. If the file system has been used for ‘a long time’ then it’s either fragmented - or it’s been defragmented and the free space is at the slow end of the drive.

One nice thing about swap partitions is that they can be fixed in place even before OS installation.

(Of course, if you’re using swap enough for this to be a huge factor, you probably have bigger problems. But I haven’t done the math.)

Indeed. I'd always put swap near the beginning, then a small root partition, then the rest. This reduced head movement for often-accessed data, and used the higher bandwidth of the outer tracks.

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