Re: [PATCH -mm] make swapin readahead skip over holes

[John Stoffel]

>>>>> "KOSAKI" == KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxx> writes:

>> Also, I doubt current swap_cluster default is best value on nowadays.
KOSAKI> I meant, current average hdd spec is,
KOSAKI>  - average seek time: 8.5ms
KOSAKI>  - sequential access performance: about 60MB/sec

KOSAKI> so, we can eat free lunch up to 7MB ~= 60(MB/sec) * 1000 / 8.5(ms).

What if the disk is busy doing other writeout or readin during this
time?  You can't assume you have the full disk bandwidth available,
esp when you hit a swap storm like this.  

John
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