Java option to generate log for class loader.

 Use option -verbose:class

to generate logs for a list of classes loaded from which jar file.

OCI: Extending the Root Partition on a Linux-Based Image

 Command to expend the root partition from default 50GB to allocated disk space while creating instance.

$ sudo /usr/libexec/oci-growfs
CHANGE: disk=/dev/sda partition=3: start=17188864 old: size=80486399,end=97675263 new: size=192526302,end=209715166
Confirm? [y/n]: y
CHANGED: disk=/dev/sda partition=3: start=17188864 old: size=80486399,end=97675263 new: size=192526302,end=209715166
	meta-data=/dev/sda3              isize=256    agcount=4, agsize=2515200 blks
	=                       sectsz=4096  attr=2, projid32bit=1
	=                       crc=0        finobt=0 spinodes=0
	data     =                       bsize=4096   blocks=10060800, imaxpct=25
	=                       sunit=0      swidth=0 blks
	naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
	log      =internal               bsize=4096   blocks=4912, version=2
	=                       sectsz=4096  sunit=1 blks, lazy-count=1
	realtime =none                   extsz=4096   blocks=0, rtextents=0
	data blocks changed from 10060800 to 24065787

Source: https://docs.oracle.com/en-us/iaas/Content/Compute/References/oci-growfs.htm#ocigrowfs

ORA-01591: lock held by in-doubt distributed transaction

 ORA-01591: lock held by in-doubt distributed transaction

If you got ” ORA-01591: lock held by in-doubt distributed transaction ” error, it means there are some uncommitted transactions in the database.

We need to perform rollback or commit force for Uncommitted transactions to solve this problem.

ORA-01591

You can query uncommitted or pending transaction with following script. This script will generate rollback force command also, so you can execute the result of following command.

SQL> select 'rollback force '''||local_tran_id||''';' from DBA_2PC_PENDING where state='prepared';

rollback force '72.6.1262301';

You can perform rollback related transaction with following command.

SQL> rollback force '72.6.1262301';

lock held by in-doubt distributed transaction

Following script will generate commit force command also, so you can execute the result of following command.

SQL> select 'commit force '''||local_tran_id||''';' from DBA_2PC_PENDING where state='prepared';

commit force '72.6.1262301';

You can perform force commit to related transaction with following command.

SQL> commit force '72.6.1262301';

Source:- https://ittutorial.org/ora-01591-lock-held-by-in-doubt-distributed-transaction/

Command to resolve display issue for Oracle Linux

xauth add `echo "${DISPLAY}" | sed 's/.*\(:.*\)/\1/'` . `mcookie`

Source: https://bbs.archlinux.org/viewtopic.php?id=98524

TMF814 Corba API Tips

 1. Use an existing holder to fetch next_n elements instead of creating a new holder for better performance.

Useful commands

• sudo netstat -tulpn | grep LISTEN 
• iostat -c

Update Ubuntu with latest packages

Steps to update packages

$ sudo apt update

$ sudo apt list --upgradable

$ sudo apt install <SPECIFIC_PACKAGE_NAME>

or

$ sudo apt upgrade