Postgresql docker SHM_SIZE/dev/SHM:调整共享内存大小
我想从默认的Postgresql docker SHM_SIZE/dev/SHM:调整共享内存大小,postgresql,docker,docker-compose,Postgresql,Docker,Docker Compose,我想从默认的64M调整postgres容器的共享内存大小。因此,我补充说: build: context: . shm_size: '2gb' 我使用的是compose文件的3.6版,postgres服务定义 version: "3.6" services: #other services go here.. postgres: restart: always image: postgres:10 hostname: postgres
64M
调整postgres
容器的共享内存大小。因此,我补充说:
build:
context: .
shm_size: '2gb'
我使用的是compose文件的3.6版,postgres
服务定义
version: "3.6"
services:
#other services go here..
postgres:
restart: always
image: postgres:10
hostname: postgres
container_name: fiware-postgres
expose:
- "5432"
ports:
- "5432:5432"
networks:
- default
environment:
- "POSTGRES_PASSWORD=password"
- "POSTGRES_USER=postgres"
- "POSTGRES_DB=postgres"
volumes:
- ./postgres-data:/var/lib/postgresql/data
build:
context: .
shm_size: '2gb'
但是,即使我重新启动服务docker compose down
然后up
,此更改也不会生效。所以,我一开始和postgres交互,在仪表板上显示一些数据,我就发现了共享内存问题
在使用仪表板之前:
$docker exec -it fiware-postgres df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/docker-253:1-107615-1541c55e4c3d5e03a7716d5418eea4c520b6556a6fd179c6ab769afd0ce64d9f 10G 266M 9.8G 3% /
tmpfs 64M 0 64M 0% /dev
tmpfs 1.4G 0 1.4G 0% /sys/fs/cgroup
/dev/vda1 197G 52G 136G 28% /etc/hosts
shm 64M 8.0K 64M 1% /dev/shm
tmpfs 1.4G 0 1.4G 0% /proc/acpi
tmpfs 1.4G 0 1.4G 0% /proc/scsi
tmpfs 1.4G 0 1.4G 0% /sys/firmware
$docker exec -it fiware-postgres df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/docker-253:1-107615-1541c55e4c3d5e03a7716d5418eea4c520b6556a6fd179c6ab769afd0ce64d9f 10G 266M 9.8G 3% /
tmpfs 64M 0 64M 0% /dev
tmpfs 1.4G 0 1.4G 0% /sys/fs/cgroup
/dev/vda1 197G 52G 136G 28% /etc/hosts
shm 64M 50M 15M 78% /dev/shm
tmpfs 1.4G 0 1.4G 0% /proc/acpi
tmpfs 1.4G 0 1.4G 0% /proc/scsi
tmpfs 1.4G 0 1.4G 0% /sys/firmware
在仪表板上吃午餐后:
$docker exec -it fiware-postgres df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/docker-253:1-107615-1541c55e4c3d5e03a7716d5418eea4c520b6556a6fd179c6ab769afd0ce64d9f 10G 266M 9.8G 3% /
tmpfs 64M 0 64M 0% /dev
tmpfs 1.4G 0 1.4G 0% /sys/fs/cgroup
/dev/vda1 197G 52G 136G 28% /etc/hosts
shm 64M 8.0K 64M 1% /dev/shm
tmpfs 1.4G 0 1.4G 0% /proc/acpi
tmpfs 1.4G 0 1.4G 0% /proc/scsi
tmpfs 1.4G 0 1.4G 0% /sys/firmware
$docker exec -it fiware-postgres df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/docker-253:1-107615-1541c55e4c3d5e03a7716d5418eea4c520b6556a6fd179c6ab769afd0ce64d9f 10G 266M 9.8G 3% /
tmpfs 64M 0 64M 0% /dev
tmpfs 1.4G 0 1.4G 0% /sys/fs/cgroup
/dev/vda1 197G 52G 136G 28% /etc/hosts
shm 64M 50M 15M 78% /dev/shm
tmpfs 1.4G 0 1.4G 0% /proc/acpi
tmpfs 1.4G 0 1.4G 0% /proc/scsi
tmpfs 1.4G 0 1.4G 0% /sys/firmware
postgres错误日志:
2019-07-01 17:27:58.802 UTC [47] ERROR: could not resize shared memory segment "/PostgreSQL.1145887853" to 12615680 bytes: No space left on device
这里发生了什么?您在
build
中设置了shm_size
,这只会影响构建,您需要在服务级别中设置它,如下一步:
docker compose.yaml:
version: "3.6"
services:
#other services go here..
postgres:
restart: always
image: postgres:10
hostname: postgres
container_name: fiware-postgres
expose:
- "5432"
ports:
- "5432:5432"
networks:
- default
environment:
- "POSTGRES_PASSWORD=password"
- "POSTGRES_USER=postgres"
- "POSTGRES_DB=postgres"
volumes:
- ./postgres-data:/var/lib/postgresql/data
build:
context: .
shm_size: 256mb
shm_size: 512mb
FROM postgres:10
RUN df -h | grep shm
Dockerfile:
version: "3.6"
services:
#other services go here..
postgres:
restart: always
image: postgres:10
hostname: postgres
container_name: fiware-postgres
expose:
- "5432"
ports:
- "5432:5432"
networks:
- default
environment:
- "POSTGRES_PASSWORD=password"
- "POSTGRES_USER=postgres"
- "POSTGRES_DB=postgres"
volumes:
- ./postgres-data:/var/lib/postgresql/data
build:
context: .
shm_size: 256mb
shm_size: 512mb
FROM postgres:10
RUN df -h | grep shm
然后,docker compose up-d--build
启动并检查:
shubuntu1@shubuntu1:~/66$ docker-compose --version
docker-compose version 1.24.0, build 0aa59064
shubuntu1@shubuntu1:~/66$ docker-compose up -d --build
Building postgres
Step 1/2 : FROM postgres:10
---> 0959974989f8
Step 2/2 : RUN df -h | grep shm
---> Running in 25d341cfde9c
shm 256M 0 256M 0% /dev/shm
Removing intermediate container 25d341cfde9c
---> 1637f1afcb81
Successfully built 1637f1afcb81
Successfully tagged postgres:10
Recreating fiware-postgres ... done
shubuntu1@shubuntu1:~/66$ docker exec -it fiware-postgres df -h | grep shm
shm 512M 8.0K 512M 1% /dev/shm
您可以在构建时看到它显示的是
256m
,但它显示的运行时容器是512m
,这是因为Postgres向共享内存写入了超过64MB的内存(Linux下为/dev/shm
)。在默认Linux设置中,最大共享内存大小为64M
我们可以使用以下命令来验证这一点:
0d807385d325:/usr/src# df -h | grep shm
shm 64.0M 0 64.0M 0% /dev/shm
我们可以通过配置docker-compose.yml like手动调整最大共享内存(将其调整为4MB,):
将其更改为4MB后,再次验证:
0d807385d325:/usr/src# df -h | grep shm
shm 4.0M 0 4.0M 0% /dev/shm
在此之后,我们无法将超过4MB的数据写入共享内存设备:
# write 4MB (1kb * 4096) to /dev/shm/test file succeeds
0d807385d325:/usr/src# dd if=/dev/zero of=/dev/shm/test bs=1024 count=4096
4096+0 records in
4096+0 records out
4194304 bytes (4.2 MB, 4.0 MiB) copied, 0.0042619 s, 984 MB/s
# write 4.001MB (1kb * 4097) to /dev/shm/test file fails
0d807385d325:/usr/src# dd if=/dev/zero of=/dev/shm/test bs=1024 count=4097
dd: error writing '/dev/shm/test': No space left on device
4097+0 records in
4096+0 records out
4194304 bytes (4.2 MB, 4.0 MiB) copied, 0.0041456 s, 1.0 GB/s
要解决此问题,我们只需将此值调整为更大的值
docker run
,我们可以使用--shm size
来调整它()
shm_size
选项对其进行如上调整()
emptyDir
选项
emptyDir
卷/dev/shm