### Most space-consuming directories
```
df -h .; du -sh -- * | sort -hr
```

### Find files newer than..

```
find . -type f -newermt 2018-01-01
```

### Sum up size from files from find:
```
find . -type f -newermt 2018-01-01 -printf "%s\n" -print0 | xargs -0 du -hc | tail -n1
```

### Clean up files in directory and compress some

```
0 1 * * * find /some/path/to/dir -type f -mtime +30 -exec rm {} \; > /dev/null 2>&1
0 1 * * * find /some/path/to/dir -type f -mtime +8 -exec gzip {} \; > /dev/null 2>&1
```

### Java expose jmx remote when not run with parameters
```
jcmd PID_HERE ManagementAgent.start jmxremote.port=SOME_PORT_HERE jmxremote.authenticate=false jmxremote.ssl=false
```

### Java run profiler for many processes
```
jps | grep PROCESS_NAME | cut -d ' ' -f1 | sed -re 's/(.+)/jcmd \1 JFR.start duration=600s filename=~\/tmp\/server-\1.jfr/' | bash
```

### Java run heapdumps for many processes
```
jps | grep PROCESS_NAME | cut -d ' ' -f1 | sed -re 's/(.+)/jmap -dump:format=b,file=server-heapdump-\1.hprof \1/' | bash
```