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What's in the realtime tree

What's in the realtime tree

Posted Oct 4, 2007 6:59 UTC (Thu) by mingo (subscriber, #31122)
Parent article: What's in the realtime tree

Nick Piggin's lockless pagecache patches have found their way into the realtime tree. These patches make a number of low-level changes to the memory management and radix tree code so that some pagecache operations can be done without taking any locks. This code has been in circulation for some time without making it into the mainline, but it seems like a win in a number of scalability situations. Another patch (by Peter Zijlstra) gets rid of the locking in the kmap() code, improving latencies in systems using high memory.

An addition to the list of credits: the -rt tree also contains Peter Zijlstra's "concurrent pagecache" patches. Nick's patches give us a concurrent "read side" pagecache, Peter's patches (which are similar in size and complexity) make the pagecache completely parallel to all concurrent users, by covering the "write side" too. [ and Peter's pagecache patchset is just az crazy as Nick's ;-) ]


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What's in the realtime tree

Posted Oct 4, 2007 7:16 UTC (Thu) by peterz (guest, #39731) [Link]

For more details on the concurrent page cache, see my OLS'07 paper:
https://ols2006.108.redhat.com/2007/Reprints/zijlstra-Rep...

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