The patch below replaces a divide by 2 with a shift -- sk_sndbuf is an integer, so gcc emits an idiv, which takes 10x longer than a shift by 1. This improves af_unix bandwidth by ~6-10K/s. Also, tidy up the comment to fit in 80 columns while we're at it.
-ben Signed-off-by: Benjamin LaHaise <[EMAIL PROTECTED]> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 1b5989b..b57d4d9 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -1427,15 +1427,15 @@ static int unix_stream_sendmsg(struct ki while(sent < len) { /* - * Optimisation for the fact that under 0.01% of X messages typically - * need breaking up. + * Optimisation for the fact that under 0.01% of X + * messages typically need breaking up. */ - size=len-sent; + size = len-sent; /* Keep two messages in the pipe so it schedules better */ - if (size > sk->sk_sndbuf / 2 - 64) - size = sk->sk_sndbuf / 2 - 64; + if (size > ((sk->sk_sndbuf >> 1) - 64)) + size = (sk->sk_sndbuf >> 1) - 64; if (size > SKB_MAX_ALLOC) size = SKB_MAX_ALLOC; - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html