From: Paolo Bonzini <pbonzini@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>,
lersek@redhat.com, qemu-devel@nongnu.org,
Wanlong Gao <gaowanlong@cn.fujitsu.com>,
Hu Tao <hutao@cn.fujitsu.com>
Subject: Re: [Qemu-devel] [PATCH v18 13/14] memory backend: fill memory backend ram fields
Date: Wed, 26 Feb 2014 14:14:27 +0100 [thread overview]
Message-ID: <530DE8B3.7070704@redhat.com> (raw)
In-Reply-To: <20140226125814.GA10055@amt.cnet>
Il 26/02/2014 13:58, Marcelo Tosatti ha scritto:
>>> I'd prefer to keep backends simple, with 1:1 mapping to memory regions.
>>
>> I agree. However not all backends may have a mapping to a RAM
>> memory region. A composite backend could create a container memory
>> region whose children are other HostMemoryBackend objects.
>>
>>> Is there a need in composite one or something similar?
>>
>> I've heard of users that want a node backed partially by hugetlbfs
>> and partially by regular RAM. Not sure why.
>
> To overcommit the non hugetlbfs backed guest RAM (think guest pagecache on that non
> hugetlbfs backed memory, swappable and KSM-able).
>
> The problem is, you have to in someway guarantee the guest allocates
> 1GB pages out of the hugetlb backed GPA ranges. Some thoughts
> (honestly, dislike all of them):
>
> 1) Boot guest with hugepages, allocate hugepages in guest,
> later on hotplug 4K backed ranges. HV-unaware reboot might fail,
> though.
>
> 2) Communicate hugepage GPAs to guest.
>
> 3) Create holes in non hugepage backed GPA range.
I guess (2) is the only one I "like", and I like it just because it
officially becomes Not Our Problem.
Paolo
next prev parent reply other threads:[~2014-02-26 13:14 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-19 7:53 [Qemu-devel] [PATCH v18 00/14] Add support for binding guest numa nodes to host numa nodes Hu Tao
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 01/14] NUMA: move numa related code to new file numa.c Hu Tao
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 02/14] NUMA: check if the total numa memory size is equal to ram_size Hu Tao
2014-02-25 13:38 ` Eric Blake
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 03/14] NUMA: Add numa_info structure to contain numa nodes info Hu Tao
2014-02-19 9:26 ` Igor Mammedov
2014-02-21 2:54 ` hu tao
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 04/14] NUMA: convert -numa option to use OptsVisitor Hu Tao
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 05/14] NUMA: expand MAX_NODES from 64 to 128 Hu Tao
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 06/14] qapi: add SIZE type parser to string_input_visitor Hu Tao
2014-02-19 9:54 ` Igor Mammedov
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 07/14] add memdev backend infrastructure Hu Tao
2014-02-19 9:15 ` Igor Mammedov
2014-02-19 7:53 ` [Qemu-devel] [PATCH v18 08/14] pc: pass QEMUMachineInitArgs to pc_memory_init Hu Tao
2014-02-19 7:54 ` [Qemu-devel] [PATCH v18 09/14] numa: introduce memory_region_allocate_system_memory Hu Tao
2014-02-19 7:54 ` [Qemu-devel] [PATCH v18 10/14] numa: add -numa node, memdev= option Hu Tao
2014-02-19 9:50 ` Igor Mammedov
2014-02-19 11:53 ` Paolo Bonzini
2014-03-04 0:10 ` Eric Blake
2014-03-04 2:20 ` Hu Tao
2014-02-19 7:54 ` [Qemu-devel] [PATCH v18 11/14] qapi: make string input visitor parse int list Hu Tao
2014-02-19 8:17 ` Hu Tao
2014-02-19 8:42 ` Paolo Bonzini
2014-02-19 7:54 ` [Qemu-devel] [PATCH v18 12/14] qapi: add HostMemPolicy enum type Hu Tao
2014-02-19 9:08 ` Paolo Bonzini
2014-02-19 11:23 ` Igor Mammedov
2014-02-19 7:54 ` [Qemu-devel] [PATCH v18 13/14] memory backend: fill memory backend ram fields Hu Tao
2014-02-19 9:03 ` Paolo Bonzini
2014-02-19 9:36 ` Igor Mammedov
2014-02-25 10:20 ` Hu Tao
2014-02-25 14:15 ` Paolo Bonzini
2014-02-26 5:00 ` Hu Tao
2014-02-26 8:47 ` Igor Mammedov
2014-02-26 8:59 ` Hu Tao
2014-02-26 12:19 ` Igor Mammedov
2014-02-26 11:22 ` Paolo Bonzini
2014-02-26 5:57 ` Hu Tao
2014-02-26 9:05 ` Paolo Bonzini
2014-02-26 9:10 ` Igor Mammedov
2014-02-26 10:33 ` Paolo Bonzini
2014-02-26 12:31 ` Igor Mammedov
2014-02-26 12:45 ` Paolo Bonzini
2014-02-26 12:58 ` Marcelo Tosatti
2014-02-26 13:14 ` Paolo Bonzini [this message]
2014-02-26 13:43 ` Igor Mammedov
2014-02-26 13:47 ` Paolo Bonzini
2014-02-26 14:25 ` Igor Mammedov
2014-02-26 14:39 ` Paolo Bonzini
2014-02-25 10:09 ` Hu Tao
2014-03-03 3:24 ` Hu Tao
2014-02-19 7:54 ` [Qemu-devel] [PATCH v18 14/14] amp: add query-memdev Hu Tao
2014-02-19 8:14 ` Hu Tao
2014-02-19 9:07 ` Paolo Bonzini
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