+The @option{merge} boolean option enables memory merge, also known as
+MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
+memory deduplication.
+
+Setting the @option{dump} boolean option to @var{off} excludes the memory from
+core dumps. This feature is also known as MADV_DONTDUMP.
+
+The @option{prealloc} boolean option enables memory preallocation.
+
+The @option{host-nodes} option binds the memory range to a list of NUMA host
+nodes.
+
+The @option{policy} option sets the NUMA policy to one of the following values:
+
+@table @option
+@item @var{default}
+default host policy
+
+@item @var{preferred}
+prefer the given host node list for allocation
+
+@item @var{bind}
+restrict memory allocation to the given host node list
+
+@item @var{interleave}
+interleave memory allocations across the given host node list
+@end table
+
+The @option{align} option specifies the base address alignment when
+QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
+@option{2M}. Some backend store specified by @option{mem-path}
+requires an alignment different than the default one used by QEMU, eg
+the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
+such cases, users can specify the required alignment via this option.
+
+@item -object memory-backend-ram,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave}
+
+Creates a memory backend object, which can be used to back the guest RAM.
+Memory backend objects offer more control than the @option{-m} option that is
+traditionally used to define guest RAM. Please refer to
+@option{memory-backend-file} for a description of the options.
+
+@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size}
+
+Creates an anonymous memory file backend object, which allows QEMU to
+share the memory with an external process (e.g. when using
+vhost-user). The memory is allocated with memfd and optional
+sealing. (Linux only)
+
+The @option{seal} option creates a sealed-file, that will block
+further resizing the memory ('on' by default).
+
+The @option{hugetlb} option specify the file to be created resides in
+the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with
+the @option{hugetlb} option, the @option{hugetlbsize} option specify
+the hugetlb page size on systems that support multiple hugetlb page
+sizes (it must be a power of 2 value supported by the system).
+
+In some versions of Linux, the @option{hugetlb} option is incompatible
+with the @option{seal} option (requires at least Linux 4.16).
+
+Please refer to @option{memory-backend-file} for a description of the
+other options.
+
projects / qemu.git / blobdiff