Kernel parameter settings in Mysql:l Flash card Linux

Configuring the Nytro warpdrive accelerator card as a file system This section describes the actions that enable you to adjust the Nytro warpdrive accelerator card to enhance the use of Oracle Linux withUnbreakable the performance of the Enterprise Kernel (UEK) operating system. These configuration steps are available in both the UEK and the Oracle Linux operating system. The following steps configure the Nytro warpdrive card as a file system for each primary server and slave server of the MySQL database. Additional options are available for doubling Nytro warpdrive acceleration and using RAID to provide fault tolerance for additional data protection.
1align the Nytro warpdrive card with the 1MB boundary in the Linux operating system. The following example shows how to use the Nytro warpdrive card partition as a single partition starting from a 1MB boundary. echo "2048,,”|Sfdisk-US/Dev/SDADisk /Dev/Sda:24321Cylinders,255Heads theSectors/trackunits=Sectors of  +Bytes, counting from 0Device Boot StartEnd#sectors Id System/Dev/Sda12048 390721535 390719488  theLinux/Dev/Sda20 - 0 0Empty/Dev/Sda30 - 0 0Empty/Dev/Sda400 - 0 0Empty
2. Bypass logging when creating the file system. With EXT-4File system and turn off logging rather than using EXT-3To eliminate the double writes to the Nytro warpdrive card in some cases. The decrease in writes improves performance and prolongs the life of the Nytrowarpdrive card.
3. Create EXT-4file system and log logging off: $ mkfs–t ext4/Dev/SDA1 or MKFS.EXT4/Dev/sda1 Create EXT-4log records are turned on by default after the file system. For validation, execute the TUNE4FS command: $ tune4fs–l/Dev/Sda1|grep ' Filesystem features ' note the "has_journal" function should be listed. To turn off logging, do: $ tune4fs-O^Has_journal/Dev/sda1
4. Verify that logging is turned off, execute the following command and make sure that "has_journal" is not listed. $ tune4fs–l/Dev/Sda1|grep ' Filesystem features '
5. Load New EXT-4Device (The following describes the Noatime option): $ mount-o Noatime/Dev/Sda1/Mountpoint
6. Modify Kernel I/O Dispatch program. I in the latest Linux OS version/O The Scheduler has a new I/O capabilities, including the option to modify these settings at startup. In the tests described in this document, DEADLINE I/O Scheduler is used with the Noatime file system load option. To invoke the DEADLINE scheduler for the entire system, add this line to the/etc/grub.conf file and restart the system. $ kernel/Vmlinuz-2.6. the-300.28.1. el6uek.x86_64 RO Root=/Dev/Mapper/Vg_nytrolv_root Elevator=Another way DEADLINE calls the DEADLINE IO Scheduler is to use the following command to modify/etc/rc.local file: $ echo "Deadline"> /Sys/Block/Sda/Queue/Scheduler
7If you want to confirm that the DEADLINE Scheduler is enabled, publish the following claims as root. $ cat/Sys/Block/Sda/Queue/Schedulernoop Anticipatory[deadline]CFQ

8. In addition to changing I/O Scheduler, the Noatime file system load option is enabled and added to the/etc/fstab file. This option eliminates the need for the system to create a write to the file system when the object is read-only. This option also allows faster access to files and reduces wear on Nytro warpdrive cards. This example describes the/etc/Fstab How to invoke the Noatime option:/Dev/Sda1/OSFC Ext4 Defaults,noatime1 2another way to invoke the Noatime option is to make this option when the load command is executed: $ mount–o noatime/Dev/Sda1/OSFC

9. The column depth (QD) from the default -Increase to theor higher (depending on the database workload), you can improve the performance of Nytro warpdrive. Since the latency of the Nytro warpdrive card is so small, the Nytro warpdrive card can run multiple I at the same time compared to the hard drive/O operation/command. To modify the row and column depth, modify the nr_requests parameter to a value that is the same or greater than the new row or column depth. The following are the modifications used in the test/Dev/examples of SDA nr_requests and Queue_depth parameters: $ echo " +”> /Sys/Block/Sda/Queue/nr_requests$ echo " +”> /Sys/Block/Sda/Device/queue_depth

Ten. By telling the operating system to complete the same CPU on which it was started/O requests can also confirm additional performance benefits. This provides significant performance improvements in some workloads. To enable this feature in the Nytro warpdrive device: echo "1”> /Sys/Block/Sda/Queue/rq_affinity
 One. Another action setting that provides higher performance is to set the rotation setting to0, which means that the device is a non-rotating device, but a flash device: Echo0 > /Sys/Block/Sda/Queue/Rotational Note: If you want to keep these settings on reboot, put all these commands into/etc/Rc.local file.

In the operating system, the I/O scheduler scheduling mode selection deadline is advantageous for the database application. Command: Echo Deadline >/sys/block//queue/scheduler

The nr_requests parameter in the operating system can improve the throughput of the system, it seems that the larger the better, but the request queue is not too large, because it consumes a lot of memory space. This value adjustment requires a combination of multiple factors,

For example: File system, Sheduler type, io characteristics.

Command: Echo xxx >/sys/block//queue/nr_requests,nr_requests Size setting is at least/sys/block/ /device/queue_depth twice times, so, modify the nr_requtests time to pay attention.

Kernel parameter settings in Mysql:l Flash card Linux