socket: bump socket buffer limit to 8MB

Bump the socket buffer limit from 2 MB to 8MB.
In particular, this allows to use larger values for TCP sockets,
which may result in higher throughput values with default settings.
In the review I was proposing using 16 MB, but in the transport
call today we settled on a more conservative value of 8.
Bumping it further will be done in combination with mitigations
for mbuf exhaustion attacks.

Reviewed by:		rscheff, Peter Lei, jtl, thj
MFC after:		3 days
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D52873

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/sys/sockbuf.h b/sys/sys/sockbuf.h
index b4593f38f592..739723754b7d 100644
--- a/sys/sys/sockbuf.h
+++ b/sys/sys/sockbuf.h
@@ -62,7 +62,7 @@
 #include <sys/_sx.h>
 #include <sys/_task.h>
 
-#define	SB_MAX		(2*1024*1024)	/* default for max chars in sockbuf */
+#define	SB_MAX		(8*1024*1024)	/* default for max chars in sockbuf */
 
 struct ktls_session;
 struct mbuf;