change hardware requirements

doc/install.md

@@ -4,8 +4,8 @@ The current version of SOCTools only runs on a single server. A fully distribute
 
 ## Hardware requirements
 * CPU: 8 cores
-* Memory: 32GB (It is possible to run on less but it is not recommended)
-* Disk: >30GB (This depends entirely on how much data you want to collect and how long you want to keep the data. For just testing SOCTools, 30GB is enough.)
+* Memory: 32GB
+* Disk: >40GB (This depends entirely on how much data you want to collect and how long you want to keep the data. For just testing SOCTools, 30GB is enough.)
 
 ## Prerequisites