Module Mapred_job_config

module Mapred_job_config: sig .. end

Extract job configuration, and marshalling

type m_job_config

val extract_job_config : Netplex_types.config_file ->
       (string * string) list ->
       string list -> Mapred_def.mapred_job_config * m_job_config

let (jc, mjc) = extract_job_config cf args custom_params:

Extracts the job configuration from cf. The association list args may contain overrides (leftmost value is taken).

Returns the configuration as object jc, and in a marshallable representation mjc.

val mapred_job_config : m_job_config -> Mapred_def.mapred_job_config

Returns the config as object

val marshal : m_job_config -> string

val unmarshal : string -> m_job_config

Marshal and unmarshal

The config file must look like (it can also contain unrelated entries):

       netplex {
         ...
         mapredjob {
           <name> = <value>;
           ...
         }
       }

The possible names are the method names of Mapred_def.mapred_job_config. The values should have the right type.

Example:

       netplex {
         mapredjob {
            name = "my_job";
            input_dir = "/input";
            output_dir = "/output";
            work_dir = "/work";
            log_dir = "/log";
            bigblock_size = 65536;
            map_tasks = 100;
            merge_limit = 4;
            split_limit = 4;
            partitions = 20;
         }
       }

Some settings have default values:

name is set to an automatically generated name
bigblock_size is 16M
map_tasks is 0 (meaning a good value is computed at runtime)
merge_limit and split_limit are 4

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