On 07/10/2015 03:33 PM, Chuck Lever wrote: > > On Jul 10, 2015, at 3:21 PM, Anna Schumaker <[email protected]> wrote: > >> Hi Chuck, >> >> On 07/09/2015 04:41 PM, Chuck Lever wrote: >>> The point of larger rsize and wsize is to reduce the per-byte cost >>> of memory registration and deregistration. Modern HCAs can typically >>> handle a megabyte or more with a single registration operation. >>> >>> Signed-off-by: Chuck Lever <[email protected]> >>> --- >>> net/sunrpc/xprtrdma/xprt_rdma.h | 3 +-- >>> 1 file changed, 1 insertion(+), 2 deletions(-) >>> >>> diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h >>> b/net/sunrpc/xprtrdma/xprt_rdma.h >>> index f49dd8b..abee472 100644 >>> --- a/net/sunrpc/xprtrdma/xprt_rdma.h >>> +++ b/net/sunrpc/xprtrdma/xprt_rdma.h >>> @@ -165,8 +165,7 @@ rdmab_to_msg(struct rpcrdma_regbuf *rb) >>> * struct rpcrdma_buffer. N is the max number of outstanding requests. >>> */ >>> >>> -/* temporary static scatter/gather max */ >>> -#define RPCRDMA_MAX_DATA_SEGS (64) /* max scatter/gather */ >>> +#define RPCRDMA_MAX_DATA_SEGS ((1 * 1024 * 1024) / PAGE_SIZE) >> ^^^ >> What is the significance of the 1 here? > > This echoes the definition of RPCSVC_MAXPAYLOAD. > > β1β documents βoneβ megabyte, I assume.
Makes sense. Thanks! > > >> Thanks, >> Anna >> >>> #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ >>> >>> struct rpcrdma_buffer; >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >>> the body of a message to [email protected] >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-rdma" in >> the body of a message to [email protected] >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- > Chuck Lever > > > -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
