Fix: Skip CSV header in monitor stats & Add randread tests (#167)

- Fix the resource monitor stats calculation to skip the CSV header line.
- Add additional 4k and 64k randread test cases to Kokoro read suite.

Author: PranjalC100

distributed-micro-benchmark/test_suites/kokoro/kokoro_read_test_cases.csv

@@ -19,6 +19,22 @@ read,1,1g,1m,1,20,1
 read,1,1g,1m,1,20,0
 read,48,1g,1m,1,20,1
 read,48,1g,1m,1,20,0
+randread,1,1g,4k,1,50,1
+randread,1,1g,4k,1,50,0
+randread,1,1g,4k,4,50,1
+randread,1,1g,4k,4,50,0
+randread,48,1g,4k,1,50,1
+randread,48,1g,4k,1,50,0
+randread,48,1g,4k,4,50,1
+randread,48,1g,4k,4,50,0
+randread,1,1g,64k,1,50,1
+randread,1,1g,64k,1,50,0
+randread,1,1g,64k,4,50,1
+randread,1,1g,64k,4,50,0
+randread,48,1g,64k,1,50,1
+randread,48,1g,64k,1,50,0
+randread,48,1g,64k,4,50,1
+randread,48,1g,64k,4,50,0
 randread,1,1g,1m,1,15,1
 randread,1,1g,1m,1,15,0
 randread,1,1g,1m,4,15,1

distributed-micro-benchmark/workers/monitor.sh

@@ -5,7 +5,7 @@
 get_col_stats() {
     local file=$1
     local col=$2
-    awk -F',' -v c="$col" '{sum+=$c; if($c>max) max=$c; count++} END {if(count>0) printf "%.2f %.2f\n", sum/count, max+0; else print "0 0"}' "$file"
+    awk -F',' -v c="$col" 'NR>1 {sum+=$c; if($c>max || max=="") max=$c; count++} END {if(count>0) printf "%.2f %.2f\n", sum/count, max+0; else print "0 0"}' "$file"
 }
 
 # Aggregates monitoring data into a single line of AVG/MAX pairs for the manifest