Container Server Configuration

This document describes the configuration options available for the container server. Documentation for other swift configuration options can be found at Configuration Documentation.

An example Container Server configuration can be found at etc/container-server.conf-sample in the source code repository.

The following configuration sections are available:

[DEFAULT]

Option

Default

Description

swift_dir

/etc/swift

Swift configuration directory

devices

/srv/node

Parent directory of where devices are mounted

mount_check

true

Whether or not check if the devices are mounted to prevent accidentally writing to the root device

bind_ip

0.0.0.0

IP Address for server to bind to

bind_port

6201

Port for server to bind to

keep_idle

600

Value to set for socket TCP_KEEPIDLE

bind_timeout

30

Seconds to attempt bind before giving up

backlog

4096

Maximum number of allowed pending connections

workers

auto

Override the number of pre-forked workers that will accept connections. If set it should be an integer, zero means no fork. If unset, it will try to default to the number of effective cpu cores and fallback to one. Increasing the number of workers may reduce the possibility of slow file system operations in one request from negatively impacting other requests. See General Service Tuning.

max_clients

1024

Maximum number of clients one worker can process simultaneously (it will actually accept(2) N + 1). Setting this to one (1) will only handle one request at a time, without accepting another request concurrently.

user

swift

User to run as

disable_fallocate

false

Disable “fast fail” fallocate checks if the underlying filesystem does not support it.

log_name

swift

Label used when logging

log_facility

LOG_LOCAL0

Syslog log facility

log_level

INFO

Logging level

log_address

/dev/log

Logging directory

log_max_line_length

0

Caps the length of log lines to the value given; no limit if set to 0, the default.

log_custom_handlers

None

Comma-separated list of functions to call to setup custom log handlers.

log_udp_host

Override log_address

log_udp_port

514

UDP log port

log_statsd_host

None

Enables StatsD logging; IPv4/IPv6 address or a hostname. If a hostname resolves to an IPv4 and IPv6 address, the IPv4 address will be used.

log_statsd_port

8125

log_statsd_default_sample_rate

1.0

log_statsd_sample_rate_factor

1.0

log_statsd_metric_prefix

eventlet_debug

false

If true, turn on debug logging for eventlet

fallocate_reserve

1%

You can set fallocate_reserve to the number of bytes or percentage of disk space you’d like fallocate to reserve, whether there is space for the given file size or not. Percentage will be used if the value ends with a ‘%’. This is useful for systems that behave badly when they completely run out of space; you can make the services pretend they’re out of space early.

db_preallocation

off

If you don’t mind the extra disk space usage in overhead, you can turn this on to preallocate disk space with SQLite databases to decrease fragmentation.

nice_priority

None

Scheduling priority of server processes. Niceness values range from -20 (most favorable to the process) to 19 (least favorable to the process). The default does not modify priority.

ionice_class

None

I/O scheduling class of server processes. I/O niceness class values are IOPRIO_CLASS_RT (realtime), IOPRIO_CLASS_BE (best-effort), and IOPRIO_CLASS_IDLE (idle). The default does not modify class and priority. Linux supports io scheduling priorities and classes since 2.6.13 with the CFQ io scheduler. Work only with ionice_priority.

ionice_priority

None

I/O scheduling priority of server processes. I/O niceness priority is a number which goes from 0 to 7. The higher the value, the lower the I/O priority of the process. Work only with ionice_class. Ignored if IOPRIO_CLASS_IDLE is set.

[container-server]

Option

Default

Description

use

paste.deploy entry point for the container server. For most cases, this should be egg:swift#container.

set log_name

container-server

Label used when logging

set log_facility

LOG_LOCAL0

Syslog log facility

set log_level

INFO

Logging level

set log_requests

True

Whether or not to log each request

set log_address

/dev/log

Logging directory

node_timeout

3

Request timeout to external services

conn_timeout

0.5

Connection timeout to external services

allow_versions

false

Enable/Disable object versioning feature

replication_server

Configure parameter for creating specific server. To handle all verbs, including replication verbs, do not specify “replication_server” (this is the default). To only handle replication, set to a True value (e.g. “True” or “1”). To handle only non-replication verbs, set to “False”. Unless you have a separate replication network, you should not specify any value for “replication_server”.

nice_priority

None

Scheduling priority of server processes. Niceness values range from -20 (most favorable to the process) to 19 (least favorable to the process). The default does not modify priority.

ionice_class

None

I/O scheduling class of server processes. I/O niceness class values are IOPRIO_CLASS_RT (realtime), IOPRIO_CLASS_BE (best-effort), and IOPRIO_CLASS_IDLE (idle). The default does not modify class and priority. Linux supports io scheduling priorities and classes since 2.6.13 with the CFQ io scheduler. Work only with ionice_priority.

ionice_priority

None

I/O scheduling priority of server processes. I/O niceness priority is a number which goes from 0 to 7. The higher the value, the lower the I/O priority of the process. Work only with ionice_class. Ignored if IOPRIO_CLASS_IDLE is set.

[container-replicator]

Option

Default

Description

log_name

container-replicator

Label used when logging

log_facility

LOG_LOCAL0

Syslog log facility

log_level

INFO

Logging level

log_address

/dev/log

Logging directory

per_diff

1000

Maximum number of database rows that will be sync’d in a single HTTP replication request. Databases with less than or equal to this number of differing rows will always be sync’d using an HTTP replication request rather than using rsync.

max_diffs

100

Maximum number of HTTP replication requests attempted on each replication pass for any one container. This caps how long the replicator will spend trying to sync a given database per pass so the other databases don’t get starved.

concurrency

8

Number of replication workers to spawn

interval

30

Time in seconds to wait between replication passes

databases_per_second

50

Maximum databases to process per second. Should be tuned according to individual system specs. 0 is unlimited.

node_timeout

10

Request timeout to external services

conn_timeout

0.5

Connection timeout to external services

reclaim_age

604800

Time elapsed in seconds before a container can be reclaimed

rsync_module

{replication_ip}::container

Format of the rsync module where the replicator will send data. The configuration value can include some variables that will be extracted from the ring. Variables must follow the format {NAME} where NAME is one of: ip, port, replication_ip, replication_port, region, zone, device, meta. See etc/rsyncd.conf-sample for some examples.

rsync_compress

no

Allow rsync to compress data which is transmitted to destination node during sync. However, this is applicable only when destination node is in a different region than the local one. NOTE: Objects that are already compressed (for example: .tar.gz, mp3) might slow down the syncing process.

recon_cache_path

/var/cache/swift

Path to recon cache

nice_priority

None

Scheduling priority of server processes. Niceness values range from -20 (most favorable to the process) to 19 (least favorable to the process). The default does not modify priority.

ionice_class

None

I/O scheduling class of server processes. I/O niceness class values are IOPRIO_CLASS_RT (realtime), IOPRIO_CLASS_BE (best-effort), and IOPRIO_CLASS_IDLE (idle). The default does not modify class and priority. Linux supports io scheduling priorities and classes since 2.6.13 with the CFQ io scheduler. Work only with ionice_priority.

ionice_priority

None

I/O scheduling priority of server processes. I/O niceness priority is a number which goes from 0 to 7. The higher the value, the lower the I/O priority of the process. Work only with ionice_class. Ignored if IOPRIO_CLASS_IDLE is set.

[container-sharder]

The container-sharder re-uses features of the container-replicator and inherits the following configuration options defined for the [container-replicator]:

  • interval

  • databases_per_second

  • per_diff

  • max_diffs

  • concurrency

  • node_timeout

  • conn_timeout

  • reclaim_age

  • rsync_compress

  • rsync_module

  • recon_cache_path

Some config options in this section may also be used by the swift-manage-shard-ranges CLI tool.

Option

Default

Description

log_name

container-sharder

Label used when logging

log_facility

LOG_LOCAL0

Syslog log facility

log_level

INFO

Logging level

log_address

/dev/log

Logging directory

auto_shard

false

If the auto_shard option is true then the sharder will automatically select containers to shard, scan for shard ranges, and select shards to shrink. Warning: auto-sharding is still under development and should not be used in production; do not set this option to true in a production cluster.

shard_container_threshold

1000000

This defines the object count at which a container with container-sharding enabled will start to shard. This also indirectly determines the initial nominal size of shard containers, which is shard_container_threshold//2, as well as determining the thresholds for shrinking and merging shard containers.

shrink_threshold

This defines the object count below which a ‘donor’ shard container will be considered for shrinking into another ‘acceptor’ shard container. The default is determined by shard_shrink_point. If set, shrink_threshold will take precedence over shard_shrink_point.

shard_shrink_point

10

Deprecated: shrink_threshold is recommended and if set will take precedence over shard_shrink_point. This defines the object count below which a ‘donor’ shard container will be considered for shrinking into another ‘acceptor’ shard container. shard_shrink_point is a percentage of shard_container_threshold e.g. the default value of 10 means 10% of the shard_container_threshold.

expansion_limit

This defines the maximum allowed size of an acceptor shard container after having a donor merged into it. The default is determined by shard_shrink_merge_point. If set, expansion_limit will take precedence over shard_shrink_merge_point.

shard_shrink_merge_point

75

Deprecated: expansion_limit is recommended and if set will take precedence over shard_shrink_merge_point. This defines the maximum allowed size of an acceptor shard container after having a donor merged into it. Shard_shrink_merge_point is a percentage of shard_container_threshold. e.g. the default value of 75 means that the projected sum of a donor object count and acceptor count must be less than 75% of shard_container_threshold for the donor to be allowed to merge into the acceptor.

For example, if shard_container_threshold is 1 million, shard_shrink_point is 10, and shard_shrink_merge_point is 75 then a shard will be considered for shrinking if it has less than or equal to 100 thousand objects but will only merge into an acceptor if the combined object count would be less than or equal to 750 thousand objects.

shard_scanner_batch_size

10

When auto-sharding is enabled this defines the maximum number of shard ranges that will be found each time the sharder daemon visits a sharding container. If necessary the sharder daemon will continue to search for more shard ranges each time it visits the container.

cleave_batch_size

2

Defines the number of shard ranges that will be cleaved each time the sharder daemon visits a sharding container.

cleave_row_batch_size

10000

Defines the size of batches of object rows read from a sharding container and merged to a shard container during cleaving.

shard_replication_quorum

auto

Defines the number of successfully replicated shard dbs required when cleaving a previously uncleaved shard range before the sharder will progress to the next shard range. The value should be less than or equal to the container ring replica count. The default of ‘auto’ causes the container ring quorum value to be used. This option only applies to the container-sharder replication and does not affect the number of shard container replicas that will eventually be replicated by the container-replicator.

existing_shard_replication_quorum

auto

Defines the number of successfully replicated shard dbs required when cleaving a shard range that has been previously cleaved on another node before the sharder will progress to the next shard range. The value should be less than or equal to the container ring replica count. The default of ‘auto’ causes the shard_replication_quorum value to be used. This option only applies to the container-sharder replication and does not affect the number of shard container replicas that will eventually be replicated by the container-replicator.

internal_client_conf_path

see description

The sharder uses an internal client to create and make requests to containers. The absolute path to the client config file can be configured. Defaults to /etc/swift/internal-client.conf

request_tries

3

The number of time the internal client will retry requests.

recon_candidates_limit

5

Each time the sharder dumps stats to the recon cache file it includes a list of containers that appear to need sharding but are not yet sharding. By default this list is limited to the top 5 containers, ordered by object count. The limit may be changed by setting recon_candidates_limit to an integer value. A negative value implies no limit.

broker_timeout

60

Large databases tend to take a while to work with, but we want to make sure we write down our progress. Use a larger-than-normal broker timeout to make us less likely to bomb out on a LockTimeout.

[container-updater]

Option

Default

Description

log_name

container-updater

Label used when logging

log_facility

LOG_LOCAL0

Syslog log facility

log_level

INFO

Logging level

log_address

/dev/log

Logging directory

interval

300

Minimum time for a pass to take

concurrency

4

Number of updater workers to spawn

node_timeout

3

Request timeout to external services

conn_timeout

0.5

Connection timeout to external services

containers_per_second

50

Maximum containers updated per second. Should be tuned according to individual system specs. 0 is unlimited.

slowdown

0.01

Time in seconds to wait between containers. Deprecated in favor of containers_per_second.

account_suppression_time

60

Seconds to suppress updating an account that has generated an error (timeout, not yet found, etc.)

recon_cache_path

/var/cache/swift

Path to recon cache

nice_priority

None

Scheduling priority of server processes. Niceness values range from -20 (most favorable to the process) to 19 (least favorable to the process). The default does not modify priority.

ionice_class

None

I/O scheduling class of server processes. I/O niceness class values are IOPRIO_CLASS_RT (realtime), IOPRIO_CLASS_BE (best-effort), and IOPRIO_CLASS_IDLE (idle). The default does not modify class and priority. Linux supports io scheduling priorities and classes since 2.6.13 with the CFQ io scheduler. Work only with ionice_priority.

ionice_priority

None

I/O scheduling priority of server processes. I/O niceness priority is a number which goes from 0 to 7. The higher the value, the lower the I/O priority of the process. Work only with ionice_class. Ignored if IOPRIO_CLASS_IDLE is set.

[container-auditor]

Option

Default

Description

log_name

container-auditor

Label used when logging

log_facility

LOG_LOCAL0

Syslog log facility

log_level

INFO

Logging level

log_address

/dev/log

Logging directory

interval

1800

Minimum time for a pass to take

containers_per_second

200

Maximum containers audited per second. Should be tuned according to individual system specs. 0 is unlimited.

recon_cache_path

/var/cache/swift

Path to recon cache

nice_priority

None

Scheduling priority of server processes. Niceness values range from -20 (most favorable to the process) to 19 (least favorable to the process). The default does not modify priority.

ionice_class

None

I/O scheduling class of server processes. I/O niceness class values are IOPRIO_CLASS_RT (realtime), IOPRIO_CLASS_BE (best-effort), and IOPRIO_CLASS_IDLE (idle). The default does not modify class and priority. Linux supports io scheduling priorities and classes since 2.6.13 with the CFQ io scheduler. Work only with ionice_priority.

ionice_priority

None

I/O scheduling priority of server processes. I/O niceness priority is a number which goes from 0 to 7. The higher the value, the lower the I/O priority of the process. Work only with ionice_class. Ignored if IOPRIO_CLASS_IDLE is set.