search for: __gfp_reclaim

On 07/11/2018 05:21 PM, Michal Hocko wrote: > On Tue 10-07-18 18:44:34, Linus Torvalds wrote: > [...] >> That was what I tried to encourage with actually removing the pages >> form the page list. That would be an _incremental_ interface. You can >> remove MAX_ORDER-1 pages one by one (or a hundred at a time), and mark >> them free for ballooning that way. And if you

On 07/11/2018 05:21 PM, Michal Hocko wrote: > On Tue 10-07-18 18:44:34, Linus Torvalds wrote: > [...] >> That was what I tried to encourage with actually removing the pages >> form the page list. That would be an _incremental_ interface. You can >> remove MAX_ORDER-1 pages one by one (or a hundred at a time), and mark >> them free for ballooning that way. And if you

...via alloc_pages, so there > > will be no new mm APIs. > > OK. The above was just a rough example. In fact you would need a more > complex gfp mask. I assume you only want to balloon only memory directly > usable by the kernel so it will be > (GFP_KERNEL | __GFP_NOWARN) & ~__GFP_RECLAIM Sounds good to me, thanks. > > > I plan to let free page allocation stop when the remaining system free > > memory becomes close to min_free_kbytes (prevent swapping). > > ~__GFP_RECLAIM will make sure you are allocate as long as there is any > memory without reclaim. It...

...n't satisfy the lowest order allocation. > >> > >> Agreed. > >> > >>> > >>> Anything else would be a huge amount of testing with all kind of > >>> workloads. > >>> > >> > >> So doing a "& ~__GFP_RECLAIM" in case order > 0? (as done in > >> GFP_TRANSHUGE_LIGHT) > > > > That will improve the situation when reclaim is not needed, but leave > > the problem in place for when it's needed: if reclaim does trigger, we > > can get a huge free page and immediate...

...ng to get free pages directly via alloc_pages, so there will be > no new mm APIs. OK. The above was just a rough example. In fact you would need a more complex gfp mask. I assume you only want to balloon only memory directly usable by the kernel so it will be (GFP_KERNEL | __GFP_NOWARN) & ~__GFP_RECLAIM > I plan to let free page allocation stop when the remaining system free > memory becomes close to min_free_kbytes (prevent swapping). ~__GFP_RECLAIM will make sure you are allocate as long as there is any memory without reclaim. It will not even poke the kswapd to do the background work. S...

...as now - when we can't satisfy the lowest order allocation. >>>> >>>> Agreed. >>>> >>>>> Anything else would be a huge amount of testing with all kind of >>>>> workloads. >>>> >>>> So doing a "& ~__GFP_RECLAIM" in case order > 0? (as done in >>>> GFP_TRANSHUGE_LIGHT) >>> >>> That will improve the situation when reclaim is not needed, but leave >>> the problem in place for when it's needed: if reclaim does trigger, we >>> can get a huge free page...

VMware balloon enhancements: adding support for memory compaction, memory shrinker (to prevent OOM) and splitting of refused pages to prevent recurring inflations. Patches 1-2: Support for compaction Patch 3: Support for memory shrinker - disabled by default Patch 4: Split refused pages to improve performance v3->v4: * "get around to" comment [Michael] * Put list_add under page lock

VMware balloon enhancements: adding support for memory compaction, memory shrinker (to prevent OOM) and splitting of refused pages to prevent recurring inflations. Patches 1-2: Support for compaction Patch 3: Support for memory shrinker - disabled by default Patch 4: Split refused pages to improve performance v3->v4: * "get around to" comment [Michael] * Put list_add under page lock

Removing the percpu_ida code nets over 400 lines of removal. It's not as spectacular as deleting an entire architecture, but it's still a worthy reduction in lines of code. Untested due to lack of hardware and not understanding how to set up a target platform. Changes from v1: - Fixed bugs pointed out by Jens in iscsit_wait_for_tag() - Abstracted out tag freeing as requested by Bart

Removing the percpu_ida code nets over 400 lines of removal. It's not as spectacular as deleting an entire architecture, but it's still a worthy reduction in lines of code. Untested due to lack of hardware and not understanding how to set up a target platform. Changes from v1: - Fixed bugs pointed out by Jens in iscsit_wait_for_tag() - Abstracted out tag freeing as requested by Bart

VMware balloon enhancements: adding support for memory compaction, memory shrinker (to prevent OOM) and splitting of refused pages to prevent recurring inflations. Patches 1-2: Support for compaction Patch 3: Support for memory shrinker - disabled by default Patch 4: Split refused pages to improve performance v2->v3: * Fixing wrong argument type (int->size_t) [Michael] * Fixing a comment

From: Matthew Wilcox <mawilcox at microsoft.com> This is a pretty rough-and-ready conversion of the target drivers from using percpu_ida to sbitmap. It compiles; I don't have a target setup, so it's completely untested. I haven't tried to do anything particularly clever here, so it's possible that, for example, the wait queue in iscsi_target_util could be more clever, like