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Writeback caching for USB sticks

Writeback caching for USB sticks

Posted Nov 17, 2011 10:15 UTC (Thu) by epa (subscriber, #39769)
Parent article: Huge pages, slow drives, and long delays

Perhaps slow devices such as USB sticks should not get writeback caching. Writes to them should happen synchronously - that would also avoid the user-unfriendly extra step of unmounting the stick before unplugging it. If you ask to copy a file to a USB stick, the OS shouldn't lie when reporting that the operation has completed; it should only say it's done when it's done.

Or at least, have at most a fixed small amount of dirty pages for removable and slow devices (those that can be written within one second, say).


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Writeback caching for USB sticks

Posted Dec 15, 2011 13:43 UTC (Thu) by hpro (subscriber, #74751) [Link]

Isn't that just backwards? The whole point of the writeback cache is to spare the user/process from having to wait for the slow write to hit disk?

On a related note, have you ever tried to do some useful work on files on a stick mounted 'sync'? It is quite painful, I assure you.

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