On Tue, Sep 28, 2010 at 01:17:33PM -0500, Nathan Fontenot wrote: > On 09/28/2010 07:38 AM, Robin Holt wrote: > > I was tasked with looking at a slowdown in similar sized SGI machines > > booting x86_64. Jack Steiner had already looked into the memory_dev_init. > > I was looking at link_mem_sections(). > > > > I made a dramatic improvement on a 16TB machine in that function by > > merely caching the most recent memory section and checking to see if > > the next memory section happens to be the subsequent in the linked list > > of kobjects. > > > > That simple cache reduced the time for link_mem_sections from 1 hour 27 > > minutes down to 46 seconds. > > Nice! > > > > > I would like to propose we implement something along those lines also, > > but I am currently swamped. I can probably get you a patch tomorrow > > afternoon that applies at the end of this set. > > Should this be done as a separate patch? This patch set concentrates on > updates to the memory code with the node updates only being done due to the > memory changes. > > I think its a good idea to do the caching and have no problem adding on to > this patchset if no one else has any objections. I am sorry. I had meant to include you on the Cc: list. I just posted a set of patches (3 small patches) which implement the cache most recent bit I aluded to above. Search for a subject of "Speed up link_mem_sections during boot" and you will find them. I did add you to the Cc: list for the next time I end up sending the set. My next task is to implement a x86_64 SGI UV specific chunk of code to memory_block_size_bytes(). Would you consider adding that to your patch set? I expect to have that either later today or early tomorrow. Robin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>