Index: usr.sbin/bsdinstall/scripts/auto
===================================================================
--- usr.sbin/bsdinstall/scripts/auto
+++ usr.sbin/bsdinstall/scripts/auto
@@ -178,6 +178,14 @@
 rm -rf $BSDINSTALL_TMPETC
 mkdir $BSDINSTALL_TMPETC
 
+# With pkgbase, pkg OOM has been observed with QEMU-default 128 MiB memory size.
+# Ensure we have at least about 256 MiB (with an allowance for rounding etc.).
+physmem=$(($(sysctl -n hw.physmem) / 1048576))
+if [ $physmem -lt 200 ]; then
+        bsddialog --backtitle "$OSNAME Installer" --title "Warning" \
+	    --msgbox "Insufficient physical memory (${physmem} MiB) detected. At least 256 MiB is recommended. The installer or installed system may not function correctly." 0 0
+fi
+
 [ -f /usr/libexec/bsdinstall/local.pre-everything ] && f_dprintf "Running local.pre-everything" && sh /usr/libexec/bsdinstall/local.pre-everything "$BSDINSTALL_CHROOT"
 
 trap true SIGINT	# This section is optional