--- illumos-gate/usr/src/uts/common/inet/tcp_impl.h.orig	2024-07-02 19:25:33.346845738 +0200
+++ illumos-gate/usr/src/uts/common/inet/tcp_impl.h	2024-07-02 20:00:05.207140717 +0200
@@ -62,9 +62,9 @@
  * by setting it to 0.
  */
 #define	TCP_XMIT_LOWATER	4096
-#define	TCP_XMIT_HIWATER	49152
+#define	TCP_XMIT_HIWATER	(1024 * 1024)
 #define	TCP_RECV_LOWATER	2048
-#define	TCP_RECV_HIWATER	128000
+#define	TCP_RECV_HIWATER	(1024 * 1024)
 
 /*
  * Bind hash list size and has function.  It has to be a power of 2 for
--- illumos-gate/usr/src/uts/common/inet/udp_impl.h.orig	2024-07-02 19:25:33.347703763 +0200
+++ illumos-gate/usr/src/uts/common/inet/udp_impl.h	2024-07-02 20:01:52.508755181 +0200
@@ -119,9 +119,9 @@
 #define	UDP_NUM_EPRIV_PORTS	64
 
 /* Default buffer size and flow control wake up threshold. */
-#define	UDP_RECV_HIWATER	(56 * 1024)
+#define	UDP_RECV_HIWATER	(1024 * 1024)
 #define	UDP_RECV_LOWATER	128
-#define	UDP_XMIT_HIWATER	(56 * 1024)
+#define	UDP_XMIT_HIWATER	(1024 * 1024)
 #define	UDP_XMIT_LOWATER	1024
 
 /*
--- illumos-gate/usr/src/uts/common/inet/tcp/tcp_tunables.c.orig	2024-07-02 20:08:02.605808960 +0200
+++ illumos-gate/usr/src/uts/common/inet/tcp/tcp_tunables.c	2024-07-03 20:19:19.173630983 +0200
@@ -461,7 +461,7 @@
 
 	{ "max_buf", MOD_PROTO_TCP,
 	    mod_set_uint32, mod_get_uint32,
-	    {8192, ULP_MAX_BUF, 1024*1024}, {1024*1024} },
+	    {8192, ULP_MAX_BUF, 2048*1024}, {2048*1024} },
 
 	{ "_strong_iss", MOD_PROTO_TCP,
 	    mod_set_uint32, mod_get_uint32,