--- mbuffer.c.orig	2018-03-15 09:04:54.000000000 -0500
+++ mbuffer.c	2018-03-15 11:52:58.000000000 -0500
@@ -42,6 +42,10 @@
 #include <sys/stat.h>
 #include <termios.h>
 
+#ifdef __FreeBSD__
+#include <sys/vmmeter.h>
+#endif
+
 
 #ifdef HAVE_SENDFILE
 #ifdef HAVE_SENDFILE_H
@@ -956,9 +960,16 @@
 		debugmsg("total # of phys pages: %li\n",NumP);
 	}
 #elif defined(__FreeBSD__)
-	size_t nump_size = sizeof(nump_size);
-	sysctlbyname("hw.availpages", &NumP, &nump_size, NULL, 0);
+	/* Get free memory average */
+	struct vmtotal vmt;
+	size_t vmt_size = sizeof(vmt);
+	if (sysctlbyname("vm.vmtotal", &vmt, &vmt_size, NULL, 0) < 0)
+		fatal("Unable to read vm.vmtotal");
+	if (vmt_size != sizeof(vmt))
+		fatal("Unable to read (wrong size) vm.vmtotal");
+	NumP = vmt.t_free;
 #endif
+	long mxnrsem = sysconf(_SC_SEM_VALUE_MAX);
 
 #ifdef _SC_PAGESIZE
 	PgSz = sysconf(_SC_PAGESIZE);
@@ -972,6 +983,8 @@
 		Blocksize = PgSz;
 		debugmsg("Blocksize set to physical page size of %u bytes\n",PgSz);
 		Numblocks = NumP/50;
+		if (mxnrsem < Numblocks)
+			Numblocks = mxnrsem;
 		debugmsg("set Numblocks to %u\n",Numblocks);
 	}
 
--- settings.c.orig	2018-03-15 10:22:55.000000000 -0500
+++ settings.c	2018-03-15 12:25:51.000000000 -0500
@@ -39,10 +39,6 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-#ifdef __FreeBSD__
-#include <sys/sysctl.h>
-#endif
-
 
 typedef enum { off, on, invalid } flag_t;
 
@@ -398,13 +394,7 @@
 	long mxnrsem;
 
 	/* check that we stay within system limits */
-#ifdef __FreeBSD__
-	size_t semvmx_size = sizeof(mxnrsem);
-	if (sysctlbyname("kern.ipc.semvmx", &mxnrsem, &semvmx_size, 0, 0) == -1)
-		mxnrsem = -1;
-#else
 	mxnrsem = sysconf(_SC_SEM_VALUE_MAX);
-#endif
 	if (-1 == mxnrsem) {
 #ifdef SEM_MAX_VALUE
 		mxnrsem = SEM_MAX_VALUE;