Increase time measurement precision (#14)

- Increases time measurement precision and update readme

README.md

@@ -1,14 +1,18 @@
 # Steps to use
 
 ## Prerequisites
-- Hadoop 2.2 or later cluster or Sandbox.
+- Hadoop 3.1 or later cluster.
 - Apache Hive.
 - Between 15 minutes and 2 days to generate data (depending on the Scale Factor you choose and available hardware).
-- Have ```gcc``` in installed your system path. If your system does not have it, install it using yum or apt-get.
+- Have the following packages. If your system does not have it, install it using apt-get or similar.
+    ```
+    bc, date, gcc, nohup, python3, timeout, zip
+    ```
 
 ## Clone
 ```
-git clone https://github.com/kcheeeung/hive-benchmark.git && cd hive-benchmark/
+git clone https://github.com/kcheeeung/hive-benchmark.git
+cd hive-benchmark/
 ```
 
 # Individual Steps

util_internalRunQuery.sh

@@ -11,7 +11,7 @@ TIME_TO_TIMEOUT=120m
 MODE='default'
 
 # Beeline command to execute
-START_TIME="$(date +%s)"
+START_TIME="$(date +%s.%N)"
 
 if [[ "${MODE}" == 'default' ]]; then
     timeout "${TIME_TO_TIMEOUT}" beeline -u "jdbc:hive2://$(hostname -f):10001/${INTERNAL_DATABASE};transportMode=http" -i "${INTERNAL_SETTINGSPATH}" -f "${INTERNAL_QUERYPATH}" &>> "${INTERNAL_LOG_PATH}"
@@ -35,10 +35,10 @@ else
     exit 1
 fi
 
-END_TIME="$(date +%s)"
+END_TIME="$(date +%s.%N)"
 
 if [[ "${RETURN_VAL}" == 0 ]]; then
-    secs_elapsed="$((END_TIME - START_TIME))"
+    secs_elapsed="$(echo "$END_TIME - $START_TIME" | bc -l)"
     echo "${INTERNAL_QID}, ${secs_elapsed}, SUCCESS" >> "${INTERNAL_CSV}"
     echo "query${INTERNAL_QID}: SUCCESS"
 else