From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Picco Date: Mon, 27 Jun 2005 21:59:21 +0000 Subject: Re: [PATCH 0/4] V3 ia64 SPARSEMEM Message-Id: <20050627215921.GC25758@localhost.localdomain> List-Id: References: <20050616132819.GP23911@localhost.localdomain> In-Reply-To: <20050616132819.GP23911@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Greg Edwards wrote: [Mon Jun 27 2005, 04:03:58PM EDT] > On Thu, Jun 16, 2005 at 09:28:19AM -0400, Bob Picco wrote: > | Tony, > | > | ChangeLog V2: > | Jesse's review input has been applied to patches 3 and 4. > | These were all cosmetic changes. > | ChangeLog V3: > | This patchset has changes for building ia64 with SPARSEMEM + > | ARCH_SPARSEMEM_EXTREME config options. The configuration options > | SECTION_BITS and PHYSICAL_MEMORY_BITS have been removed and are > | like other arches (not configurable). > | > | This patchset depends on SPARSEMEM EXTREME patches submitted to -mm. > | The -mm patch sparsemem-extreme.patch and all those which it depends > | on are required. EXTREME has introduced a two dimensional array > | to SPARSEMEM. The two level layout should reduce memory requirements > | for extremely sparse memory at the expense of an additional load > | and shift when fetching the section map for a page frame. > | > | The only C code change since V2 is in patch 4. SPARSEMEM's > | routine memory_present, for identifying a section with memory, is > | called in paging_init instead of find_memory. This is required > | because EXTREME uses the bootmem allocator for the root level > | allocations in the new two level layout scheme. > | > | I have gathered OSDL aim7 data on an rx2600 4Gb of memory and two > | CPUs. The data is for SPARSEMEM+EXTREME and DISCONTIG+VIRTUAL_MEM_MAP. > | This obviously isn't conclusive data for the adoption of ia64 > | SPARSEMEM but does demonstrate no degradation on a small server. I'll > | need Jack's help to gather more supporting performance data. > | > | This is a series of patches which enable SPARSEMEM for ia64. It's against > | rc4-mm2. The patches have been tested against memory configurations FLATMEM, > | DISCONTIG and SPARSEMEM+EXTREME. This includes NUMA simulated hardware, rx2600 > | and HPSIM. An early version of ia64 with SPARSEMEM was tested by Jesse. It > | would be optimal to have another test pass on SGI NUMA hardware. > > Bob, > > I did a few aim7 runs of SPARSEMEM+EXTREME vs DISCONTIG+VIRTUAL_MEM_MAP > with 2.6.12-mm1 on a 128p Altix. There wasn't a noticeable difference > between the two, so I think we're good to go. > > Greg Greg, Thanks! bob