Shulou(Shulou.com)06/01 Report--

At the beginning of this year, in order to do the performance test of the all-in-one machine and the storage performance test of CRM3.0, we quickly did some knowledge about storage, and combined with Swingbench and fio, we did some testing work on database and storage performance.

The whole IO stack is a complex process, including software and hardware-related content.

Original address of the picture: http://www.ilinuxkernel.com/files/Linux.IO.stack_v1.0.pdf

Limited to its own knowledge system, only a general understanding of the basic technical environment

Unfortunately, the original origin of this picture cannot be found, and the query from google can help us understand which devices flow through from the database initiating the IO request operation to the final completion of the data operation.

The knowledge content related to the database has been organized into "X86 platform RAC installation Best practices", which has been shared in the activities of the ORACLE user group.

In order to understand the device delay, a copy of request delay data for different devices is compiled based on Intel Xeon E5 CPU.

System equipment

Real delay

Zoom delay

A CPU instruction

0.4 ns

1 s

CPU Level 1 cach

0.9 ns

2 s

CPU Level 2 cach

2.8 ns

7 s

CPU Level 3 cach

28 ns (10 X L2)

1 min

DDR memory

100 ns

4 min

Intel is arrogant.

.. /.. / devices/pci0000:c0/0000:c0:03.0/0000:c1:00.0/host3/fc_host/host3

Storage front-end port number

[root@dzqddb1 ~] # cd / sys/class/fc_remote_ports

Rport-3:0-0->.. /.. / devices/pci0000:c0/0000:c0:03.0/0000:c1:00.0/host3/rport-3:0-0/fc_remote_ports/rport-3:0-0

Disk device mapping path

[root@dzqddb1] # udevadm info-- query=all-- name=/dev/sdak

P: / devices/pci0000:c0/0000:c0:03.0/0000:c1:00.0/host3/rport-3:0-1/target3:0:1/3:0:1:12/block/sdak

Including the comparison of some disk parameters:

Mechanical hard disk (HDD)

Solid state hard drive (SSD)

NVMe SSD

Product

Seagate ST4000DM006

INTEL SSD 545S

Intel SSD DC P4600

Interface Typ

SATA 6Gb/s

6 Gb/s SATA interface

PCIe NVMe 3.1 x4

Capacity

4TB

1.00 TB

4.00 TB

Sequential reading

220MB/s

550 MB/s

3200 MB/s

Random reading

seventy-six

85000

617500

Sequential writing

500 MB/s

1900 MB/s

Random writing

75000

225000

Read delay

9 ms

50 μ s

82 μ s

Write delay

9 ms

50 μ s

30 μ s

Price

700 yuan

1500 yuan

19000 yuan

Recommend a set of videos from Aliyun, "in-depth analysis of the principle and evolution of data storage technology", which is very exciting. Https://yq.aliyun.com/promotion/689, but the data of online video streaming is a bit slow. If you want to download the video, you can download the offline version with Baidu network disk:

Link: https://pan.baidu.com/s/1FEq6mtD4x8e2UDqeqIs8Bg

Extraction code: kyq2

The other two collated documents are also shared on the network disk.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.