mfschunkserver.cfg man page

mfschunkserver.cfg — main configuration file for *mfschunkserver*

Description

The file mfschunkserver.cfg contains configuration of LizardFS chunkserver process.

Syntax

Syntax is:

OPTION = VALUE

Lines starting with # character are ignored.

Options

Configuration options:

DATA_PATH

where to store files with usage statistics and daemon lock file

LABEL

the label of this chunkserver (for tiering)

WORKING_USER

user to run daemon as

WORKING_GROUP

group to run daemon as (optional - if empty then default user group will be used)

SYSLOG_IDENT

name of process to place in syslog messages (default is mfschunkserver)

LOCK_MEMORY

whether to perform mlockall() to avoid swapping out mfschunkserver process (default is 0, i.e. no)

NICE_LEVEL

nice level to run daemon with (default is -19 if possible; note: process must be started as root to increase priority)

MASTER_HOST

address of LizardFS master host to connect with (default is mfsmaster)

MASTER_PORT

number of LizardFS master port to connect with (default is 9420)

MASTER_RECONNECTION_DELAY

delay in seconds before trying to reconnect to the master server after disconnection (default is 5)

MASTER_TIMEOUT

timeout (in seconds) for the master server connection (default is 60, minimum is 0.01)

BIND_HOST

local address to use for connecting with the master server (default is *, i.e. default local address)

CSSERV_LISTEN_HOST

IP address to listen on for client (mount) connections (* means any)

CSSERV_LISTEN_PORT

port to listen on for client (mount) connections (default is 9422)

CSSERV_TIMEOUT

timeout (in seconds) for client (mount) connections (default is 5)

HDD_CONF_FILENAME

alternative name of mfshdd.cfg file

HDD_LEAVE_SPACE_DEFAULT

free space threshold to set volume as 100% utilized when there is less than given amount of free space left (default is "4GiB"). This number is always added to the used disk space reported by chunkserver.

HDD_TEST_FREQ

chunk test period in seconds (default is 10)

HDD_ADVISE_NO_CACHE

whether to remove each chunk from page when closing it to reduce cache pressure generated by chunkserver (default is 0, i.e. no)

HDD_PUNCH_HOLES

if enabled then chunkserver detects zero values in chunk data and frees corresponding file blocks (decreasing file system usage). This option works only on Linux with file systems supporting punching holes (XFS, ext4, Btrfs, tmpfs)

ENABLE_LOAD_FACTOR

if enabled, chunkserver will send periodical reports of its I/O load to master, which will be taken into consideration when picking chunkservers for I/O operations.

REPLICATION_BANDWIDTH_LIMIT_KBPS

limit how many kilobytes can be replicated from other chunkservers to this chunkserver in every second (by default undefined, i.e. no limits)

NR_OF_NETWORK_WORKERS

number of threads which handle (in a round-robin manner) connections with clients (default is 1); these threads are responsible for reading from sockets and coping data from internal buffers to sockets

NR_OF_HDD_WORKERS_PER_NETWORK_WORKER

number of threads that each network worker may use to do disk operations like opening chunks, reading or writing them (default is 2)

READ_AHEAD_KB

additional number of kilobytes which should be passed to posix_fadvise(POSIX_FADV_WILLNEED) before reading data from a chunk (default is 0, i.e. use posix_fadvise only with the amount of data that is really needed; the value is aligned down to 64 KiB)

MAX_READ_BEHIND_KB

try to fix out-of-order read requests; the value tells how much of skipped data to read if an offset of some read operation is greater than the offset where the previos operation finished (default is 0, i.e. don’t read any skipped data; the value is aligned down to 64 KiB)

CREATE_NEW_CHUNKS_IN_MOOSEFS_FORMAT

whether to create new chunks in the MooseFS format (signature + <checksum>* + <data block>*) or in the newer interleaved format ([<checksum> <data block>]*). (Default is 1, i.e. new chunks are created in MooseFS format)

PERFORM_FSYNC

call fsync() after a chunk is modified (default is 1, i.e. enabled)

See Also

mfschunkserver(8), mfshdd.cfg(5)

Referenced By

mfschunkserver(8), mfsgoals.cfg(5), mfshdd.cfg(5).

08/27/2017