On Wed, Apr 1, 2009 at 10:08 AM, Peter Teoh <htmldeveloper@xxxxxxxxx> wrote: > based on http://lwn.net/Articles/229984/, which explained the > differences in some ways, my understanding is that SLUB is targetting > for large number of CPUs/nodes. For machines like 2 or 4 cores, it > should not matters much, correct? (or possibly higher overheads in > some scenario?) I think, SLUB is created primarily to deal with NUMA machines (I also read this from your mentioned LWN page). Thus, it maintains locality as good as it could. The same page also mentions "preventing cache line bouncing", which convince me more about my vague conclusion About SLOB, I believe it's targetting embedded device, as written in this page http://lwn.net/Articles/157944/. SLOB implementation is way simpler compared to SLAB and the cache management itself, at least after I read the code briefly, is simple. So the key words here are: small code, small memory footprints. Now....hmm, SLQB ... i hit google and found this http://linux.derkeiler.com/Mailing-Lists/Kernel/2009-01/msg06324.html. >From this paragraph: "SLQB: A slab allocator that focuses on per-CPU scaling, and good performance * with order-0 allocations. Fast paths emphasis is placed on local allocaiton * and freeing, but with a secondary goal of good remote freeing (freeing onthat allocation is done in FIFO style * another CPU from that which allocated)" I draw another (sorry peter :) ) vague conclusion that it manages to optimize the fast paths when dealing with local allocation. Why? probably because Nick Piggin thinks the other allocators are not doing good in this aspect, while most application would certainly be given free pages for the same node. Another keywords that I read on that page is the term "using queue", which lead me think that the queue might be implemented on per CPU per node basis. Otherwise, scalability won't be good IMO. What do you guys think? regards, Mulyadi. -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
