add mixed load test, other fixes
diff --git a/wally/suits/io/mixed_ssd.cfg b/wally/suits/io/mixed_ssd.cfg
new file mode 100644
index 0000000..2e9f04c
--- /dev/null
+++ b/wally/suits/io/mixed_ssd.cfg
@@ -0,0 +1,12 @@
+[global]
+include defaults.cfg
+ramp_time=5
+runtime=30
+blocksize=4k
+rw=randrw
+sync=1
+direct=1
+
+[mixed-ssd-r{rwmixread}_{TEST_SUMM}]
+rwmixread={% 0,20,40,60,80,85,90,95,100 %}
+numjobs={% 1,16,64,128 %}