3942 inject sanity into ipadm tcp buffer size properties
3943 _snd_lowat_fraction tcp tunable has no effect
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Peng Dai <peng.dai@delphix.com>

@@ -20,10 +20,11 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011, Joyent Inc. All rights reserved.
  * Copyright (c) 2013, OmniTI Computer Consulting, Inc. All rights reserved.
+ * Copyright (c) 2013 by Delphix. All rights reserved.
  */
 
 #ifndef _INET_TCP_IMPL_H
 #define _INET_TCP_IMPL_H
 

@@ -52,10 +53,21 @@
 extern struct qinit     tcp_winit;
 
 extern sock_downcalls_t sock_tcp_downcalls;
 
 /*
+ * Note that by default, the _snd_lowat_fraction tunable controls the value of
+ * the transmit low water mark.  TCP_XMIT_LOWATER (and thus the _xmit_lowat
+ * property) is only used if the administrator has disabled _snd_lowat_fraction
+ * by setting it to 0.
+ */
+#define TCP_XMIT_LOWATER        4096
+#define TCP_XMIT_HIWATER        49152
+#define TCP_RECV_LOWATER        2048
+#define TCP_RECV_HIWATER        128000
+
+/*
  * Bind hash list size and has function.  It has to be a power of 2 for
  * hashing.
  */
 #define TCP_BIND_FANOUT_SIZE    1024
 #define TCP_BIND_HASH(lport) (ntohs(lport) & (TCP_BIND_FANOUT_SIZE - 1))