On 04/05/2012 01:47 PM, Orit Wasserman wrote:
> Change XBZRLE cache size in MB (the size should be a power of 2).
In bytes
>
> +void xbzrle_cache_resize(int64_t new_size)
> +{
> + if (page_cache) {
> + cache_fini();
> + cache_init(new_size);
> + }
> +}
A little sad to drop the cache, especially if we're enlarging it. But
this can be improved later.
> +
> +ETEXI
> +
> + {
> + .name = "migrate_set_cachesize",
> + .args_type = "value:o",
> + .params = "value",
> + .help = "set cache size (in MB) for XBZRLE migrations",
In bytes.
> + .mhandler.cmd = hmp_migrate_set_cachesize,
> + },
> +
> +STEXI
> +@item migrate_set_cachesize @var{value}
> +@findex migrate_set_cache
> +Set cache size to @var{value} (in MB) for xbzrle migrations.
Need to document the constraints, and say something about how a larger
cache size can reduce the needed bandwidth.
We need to either document the default or (better) add a command to get
the current cache size (perhaps with some statistics about hit rate and
average data reduction).
>
> +void qmp_migrate_set_cachesize(int64_t value, Error **errp)
> +{
> + MigrationState *s;
> +
> + /* On 32-bit hosts, QEMU is limited by virtual address space */
> + if (value > (2047 << 20) && HOST_LONG_BITS == 32) {
Could be made clearer by using
/* Check for truncation */
if (value != (size_t)value)) {
...
(assumes value is in bytes)
> ##
> +# @migrate_set_cachesize
> +#
> +# Set XBZRLE cache size
> +#
> +# @value: cache size in bytes
Here it's in bytes, good.
For the human monitor we can use MB as the unit, or allow suffixes as we
do for -m <memory>.
--
error compiling committee.c: too many arguments to function
