ERROR 2006 (HY000) at line 257: MySQL server has gone away When doing a mysql dump to the database, if you get this error, it means that you have a connection timeout on the database or your restore is doing a chunk of data that exceeds the max allowed packets. Solution: If you are on… Continue reading ERROR 2006 (HY000) at line 257: MySQL server has gone away
Find the database size of each database Run the below query at the mysql prompt SELECT table_schema “Data Base Name”, sum( data_length + index_length ) / 1024 / 1024 “Data Base Size in MB”, sum( data_free )/ 1024 / 1024 “Free Space in MB” FROM information_schema.TABLES GROUP BY table_schema ;
Find the process Id of the java process In linux. Go to command line. ps aux | grep ‘java’ To generate the dump. jmap -dump:format=b,file=/tmp/heapdump-001.hprof <process id> $ jmap -dump:format=b,file=/tmp/heapdump-001.hprof 31467 Dumping heap to /tmp/heapdump-001.hprof … Heap dump file created The dump file wil be generated at /tmp/heapdump-001.hprof. $ ls -al… Continue reading How to generate JVM Heap dump
advanced use of grep
Booting up linux.. What is behind the scenes… ?