mfschunkserver.cfg
Every option of mfschunkserver.cfg, the configuration file of a Chunkserver. Lines starting with # are comments, and one line sets one option:
OPTION = VALUE
An option the file does not set takes the default value from this table. A dash stands for an option with no default: what it configures stays off until you set it.
A path, a user name or a port number below is the value the packages are built with. If you build MooseFS yourself, configure sets that value. See values set at build time.
Startup options
Changes in this section require process restart.
| Option | Default | Description |
|---|---|---|
mfs | User to run daemon as. | |
mfs | Group to run daemon as (optional - if empty then default user group will be used). | |
mfschunkserver | Name of process to place in syslog messages. | |
0 | Whether to perform mlockall() to avoid swapping out mfschunkserver process (0, i.e. no). | |
4 | Linux only: limit malloc arenas to given value - prevents server from using huge amount of virtual memory. | |
1 | Linux only: disable out of memory killer. | |
-19 | Nice level to run daemon with (note: process must be started as root to increase priority, if setting of priority fails, process retains the nice level it started with). | |
027 | Set default umask for group and others (user has always 0, 027 - block write for group and block all for others). | |
/var/lib/mfs | Where to store daemon lock file and metadata files. | |
0 | When set to one chunkserver will not abort start even when incorrect entries are found in 'mfshdd.cfg' file. | |
0 | Using mmap for allocation can slightly reduce ram usage and give a slight performance boost, but on certain architectures/kernels can lead to problems. |
Runtime options
Changes in this section require only process reload.
| Option | Default | Description |
|---|---|---|
/etc/mfs/mfshdd.cfg | Alternate location/name of mfshdd.cfg file; this file will be re-read on each process reload, regardless if the path was changed. | |
1.0 | Speed of background chunk tests in MiB/s per disk (formally entry defined in mfshdd.cfg). Value can be given as a decimal number; deprecates: HDD_TEST_FREQ (if HDD_TEST_SPEED is not defined, but there is redefined HDD_TEST_FREQ, then HDD_TEST_SPEED = 10 / HDD_TEST_FREQ). | |
1d | Do not test a chunk's integrity when last I/O (including test) on this chunk was performed less than HDD_MIN_TEST_INTERVAL ago; time can be defined as a number of seconds (integer) or a time period in one of two possible formats: first format: #.#T where T is one of: s-seconds, m-minutes, h-hours, d-days or w-weeks; fractions of seconds will be rounded to full seconds second format: #w#d#h#m#s, any number of definitions can be omitted, but the remaining definitions must be in order (so #d#m is still a valid definition, but #m#d is not); ranges: s,m: 0 to 59, h: 0 to 23, d: 0 to 6, w is unlimited and the first definition is also always unlimited (i.e. for #d#h#m d will be unlimited). | |
256MiB | How much space should be left unused on each hard drive; number format: [0-9]([.][0-9])?([kMGTPE]|[KMGTPE]i)?B? examples: 0.5GB;.5G; 2.56GiB; 1256M etc. | |
20 | Percent of total work time the chunkserver is allowed to spend on hdd space rebalancing. | |
0 | Maximum simultaneous writes per disk in high speed disk rebalance (0 means use standard rebalance). | |
2 | How many i/o errors (COUNT) to tolerate in given amount of seconds (PERIOD) on a single hard drive; if the number of errors exceeds this setting, the offending hard drive will be marked as damaged. | |
600 | How many i/o errors (COUNT) to tolerate in given amount of seconds (PERIOD) on a single hard drive; if the number of errors exceeds this setting, the offending hard drive will be marked as damaged. | |
0 | Consider i/o operations, that last more than N seconds, as i/o errors; 0 (default) disables this option. | |
0 | Enables/disables fsync before chunk closing. | |
1 | Enables/disables sparsification (skip zeros) during write. | |
10000 | How many chunks should be created in one directory before moving to the next one (higher values are better with most OSes caching algorithms, low values lead to more even chunk distribution, 10000 which works best in most cases). | |
1w | How long duplicate chunks should be kept before deleting; time can be defined as a number of hours (integer) or a time period in one of two possible formats: first format: #.#T where T is one of: h-hours, d-days or w-weeks; fractions of hours will be rounded to full hours second format: #w#d#h, any number of definitions can be omitted, but the remaining definitions must be in order (so #w#h is still a valid definition, but #h#w is not); ranges: h: 0 to 23, d: 0 to 6, w is unlimited and the first definition is also always unlimited (i.e. for #d#h d will be unlimited). | |
250 | Maximum number of active workers and maximum number of idle workers. | |
40 | Maximum number of active workers and maximum number of idle workers. | |
INFO | Minimum level of messages that will be reported by chunkserver; levels in order of importance: ERROR, WARNING, NOTICE, INFO, DEBUG. | |
NOTICE | Reported messages of level lower than set here will be elevated to this level (i.e. if SYSLOG_MIN_LEVEL is set to DEBUG and SYSLOG_ELEVATE_TO is set to NOTICE, all INFO and DEBUG messages will be sent to syslog as NOTICE). |
Master connection options
Changes in this section require only process reload.
| Option | Default | Description |
|---|---|---|
| not set | Labels string (empty - no labels); labels should be defined as a set of letters (case insensitive) separated by ',' or ';'. | |
* | Local address to use for master connections (*, i.e. default local address). | |
mfsmaster | MooseFS master host, IP is allowed only in single-master installations. | |
9420 | MooseFS master chunkserver port. | |
| PRO (PRO Edition only) | 9419 | MooseFS master control (supervisor) port. |
0 | Timeout in seconds for master connections. Value >0 forces given timeout, but when value is 0 then CS asks master for timeout (0 - ask master). | |
5 | Delay in seconds before next try to reconnect to master if not connected. | |
| not set | Authentication string (used only when master requires authorization). | |
1000 | Maximum number of chunks system will try to put in a single register message (limits 100-10000). |
Clients connection options
Changes in this section require only process reload.
| Option | Default | Description |
|---|---|---|
* | IP address to listen for client (mount) connections (* means any). | |
9422 | Port to listen for client (mount) connections. |