Linux Server Performance Analyzer Utilities

If there is any Linux performance issue we mostly go to Google and find commands to analyze the performance but multiple time it's difficult to find it when we required some specific details so, we have tried here to place all the Linux performance utility which can help you to analyze the Linux server performance.

There are multiple utilities available to analyse Linux server. Which includes CPUs, Memory, I/O, disk, network analysis.


UtilityDiscription
free Displays free and used memory.
iostat Displays disk I/O statistics.
netstat Reports on network statistics.
mpstat Reports CPU statistics.
vmstat Monitors processes, CPU, memory, or disk I/O bottlenecks.
ps Identifies highest CPU- and memory-consuming sessions. Used to identify Oracle
sar Displays CPU, memory, disk I/O, and network usage, both current and historical
top Identifies sessions consuming the most resources.
watch Periodically runs another command.
du Displays disk usage.
df Reports on free disk space.

                                              How to calculate IOPS in Exadata ?

Oracle Database In-Memory (DBIM)

Let's first understand why DBIM is revolutionized...

Generally Organization keeps different database for Reporting and Application Transaction because of the performance issues so whenever any transactions happen to the Application Transaction database it will immediately replicate to report database which help to get up date data while fetching report from the reporting database.

Business don't want to access same database for reporting and transaction because of the performance impact on single DB as mixed workload can slow the database and  that's why they prefer to keep separate database for both activity which gives overhead of h/w & s/w management, required more resources to handle both environment and ultimately it will  increase TCO at the end of day.

To overcome from this situation Oracle comes with DBIM (Database In Memory) which keeps frequently accessed data in memory to get faster response and decrease the response time by eliminating disk IO. It will store Database in storage only but it will store most accessible data in memory which gives faster response compare to read from disk. We can also influence object which we want to keep in memory.

Exadata Dictionary Views

Listed down some Exadata views which can help you to get Exadata related statistics

Get Cell Definition

V$CELL 
GV$CELL 

Exadata cell effectiveness and statistics

V$SYSSTAT 

V$SEGMENT_STATISTICS 

V$SQL 

Historical view of the types and frequencies of the requests being run by a cell.

V$CELL_REQUEST_TOTALS 

Cell Performance Statistics

V$CELL_STATE 

Display Exadata Cell Threads

V$CELL_THREAD_HISTORY

Backup Related View

V$BACKUP_DATAFILE 

Useful Files in Solaris

Message log:  /var/adm/messages

Tape driver configuration file:  /kernel/drv/st.conf

Disk driver configuration file:  /kernel/drv/sd.conf

File defining filesystems to mount:  /etc/vfstab

Kernel configuration parameters:  /etc/system

Names and IP addr of machines:  /etc/hosts

Default Port Numbers:  /etc/services

                                    Analyze Linux Server Performance

How to check that database is running on Exadata?

All the DBA don't get chance to work on Exadata as only DMA would have access to the Exadata so , if you are a DBA and want to know that whether your database is running on Exadata or not than you can check with below query.

If this query gives the output >0 than database is running on Exadata.

SQL>select count(*) from (select distinct cell_name from gv$cell_state);

COUNT(*)
------------
         3

It means database is running on 1/8th Exadata as 3 tells you the number of cells available on database machine.

By executing "select distinct cell_name from gv$cell_state" you will get cell IP details.

How to change password of CISCO switch on Exadata ?

Login and telnet to cisco switch

$ telnet 

Enable command line for switch

telnet> enable

Prepare to configure switch

ciscoswitch-ip# configure terminal
exapsw-ip(config)#line vty 0 15
exapsw-ip(config-line)#login

Change the password

exapsw-ip(config-line)#password newpassword
exapsw-ip(config-line)#login
exapsw-ip(config-line)#end

Save the changes to the switch

exapsw-ip#write memory
Building configuration…
Compressed configuration from 4001 bytes to 1608 bytes[OK]
exapsw-ip#

Now try to login again with new password to verify the changed password

Password Aging in Linux

Disable Password Aging

#chage -M 99999 user_name

To get password expiration information

#chage -l user_name

To change aging

# chage -M 60 -m 7 -W 7 user_name

Here,

Minimum_days (M): The minimum number of days required between password changes i.e. the number of days left before the user is allowed to change his/her password.

Maximum_days(m): The maximum number of days the password is valid (after that user is forced to change his/her password).

Warn (W) : The number of days before password is to expire that user is warned that his/her password must be changed.

Oracle Exadata vs SAP HANA

We have provided some major difference between SAP HANA and Oracle Exadata. 

Even Exadata is not comparable with HANA than also we have tried to conclude it based on materials and documentation available in the market.

Oracle Exadata
SAP HANA
SAP HANA is an in-Memory Appliance. SAP HANA is an in-Memory Appliance.
Oracle Exadata is based on Oracle servers, storage, networking, and software– all engineered and optimized to work together.

It’s meant for Mixed workloads, i.e OLTP,DW
SAP HANA and partner solutions powered by the SAP HANA in-memory software.

There are only a limited number of specialized SAP applications that run on HANA
We can use existing Oracle licences with Exadata If we move to HANA, it's required to buy new licences as existing licences would not be reused
Oracle Exadata is delivered pre-configured, pre-tested and pre-optimized, with all necessary software, storage, hardware,and interconnect to lower total cost of ownership and provide quick time to value.

Oracle Exadata is sold, delivered, and supported as a single-vendor solution with quick time-to-resolution.
SAP HANA relies on third-party compute, network,and storage vendors. Multiple points of support lead to longer downtimes and higher total cost of ownership.

No single vendor is accountable for the solution's service-level agreements and due to its complexity, HANA deployments typically require a significant amount of effort.
Exadata can be used for any type of workload for any application which is running with Oracle Database HANA is limited to SAP BW only. It doesn't support any other application
Exadata is capable for all type of workload so customer can consolidate multiple database on single machine. SAP HANA runs only single application. It doesn't support multiple workload as well non sap DBs
Exadata comes with built in security HANA don't have any encryption, auditing , compliance monitoring or any security certification
Oracle Exadata is enough smart to use RAM, Flash and Storage HANA puts everything on memory
Exadata is single vendor optimized machine HANA comes as an assemble hardware
Exadata is pre configured with HA and single point of hardware failure HANA has limited capabilities in backup and recovery area. Also there is no failover solution as well disaster recovery solution
We can use IORM and instance caging in Exadata to prioritize the I/Os. There is no features available to prioritize I/O in HANA
TCO is less compare to HANA TCO is high compare to Exadata
Only Exadata DBA is required to manage Exadata Multiple resource required to manage HANA
You can follow our Exadata Certification Question Bank to achieve maximum success in your Exadata certification.