The size of struct fuse_req was reduced from 392B to 144B on a non-debug
config, thus the sanitize_global_limit() helper was setting a larger
default limit. This doesn't really reflect reduction in the memory used by
requests, since the fields removed from fuse_req were added to fuse_args
derived structs; e.g. sizeof(struct fuse_writepages_args) is 248B, thus
resulting in slightly more memory being used for writepage requests
overalll (due to using 256B slabs).
Make the calculatation ignore the size of fuse_req and use the old 392B
value.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
static void sanitize_global_limit(unsigned *limit)
{
+ /*
+ * The default maximum number of async requests is calculated to consume
+ * 1/2^13 of the total memory, assuming 392 bytes per request.
+ */
if (*limit == 0)
- *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) /
- sizeof(struct fuse_req);
+ *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392;
if (*limit >= 1 << 16)
*limit = (1 << 16) - 1;