[libvirt] [PATCH] Qemu: ask for memory preallocation with large pages

Daniel Veillard veillard at redhat.com
Thu Jan 7 13:53:20 UTC 2010


The -mem-prealloc flag should be used when using large pages
This ensures qemu tries to allocate all required memory immediately,
rather than when first used. The latter mode will crash qemu
if hugepages aren't available when accessed, while the former
should gracefully fallback to non-hugepages.

* src/qemu/qemu_conf.c: add -mem-prealloc flag to qemu command line
  when using large pages

Daniel

diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index 824055f..d3da776 100644
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -2108,6 +2108,7 @@ int qemudBuildCommandLine(virConnectPtr conn,
                              def->emulator);
             goto error;
         }
+        ADD_ARG_LIT("-mem-prealloc");
         ADD_ARG_LIT("-mem-path");
         ADD_ARG_LIT(driver->hugepage_path);
     }

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
daniel at veillard.com  | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library  http://libvirt.org/




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