Doc updates

``linger.ms``

  Linger time in milliseconds for batching.

  Records that arrive in between request transmissions are batched into a single bulk indexing request, based on the ``batch.size`` configuration. Normally this only occurs under load when records arrive faster than they can be sent out. However it may be desirable to reduce the number of requests even under light load and benefit from bulk indexing. This setting helps accomplishes that - rather than immediately sending out a record, the task will wait upto the given delay to allow other records to be added so that they can be batched into a single request.

  Records that arrive in between request transmissions are batched into a single bulk indexing request, based on the ``batch.size`` configuration. Normally this only occurs under load when records arrive faster than they can be sent out. However it may be desirable to reduce the number of requests even under light load and benefit from bulk indexing. This setting helps accomplish that - when a pending batch is not full, rather than immediately sending it out the task will wait up to the given delay to allow other records to be added so that they can be batched into a single request.

  * Type: long

  * Default: 1

  * Importance: low

``flush.timeout.ms``

  The timeout in milliseconds when flushing records to Elasticsearch.

  The timeout in milliseconds to use for periodic flushing, and when waiting for buffer space to be made available by completed requests as records are added. If this timeout is exceeded the task will fail.

  * Type: long

  * Default: 10000

  * Importance: medium

``max.retries``

  The maximum number of retries that are allowed.

  The maximum number of retries that are allowed for failed indexing requests. If the retry attempts are exhausted the task will fail.

  * Type: int

  * Default: 5

  * Importance: low

``retry.backoff.ms``

  How long to wait in milliseconds, before attempting to retry a failed batch. This avoids retrying requests in a tight loop under certain failure scenarios.

  How long to wait in milliseconds before attempting to retry a failed indexing request. This avoids retrying in a tight loop under failure scenarios.

  * Type: long

  * Default: 100

                  + "Records that arrive in between request transmissions are batched into a single bulk indexing request, based on the ``" + BATCH_SIZE_CONFIG + "`` configuration. "

                  + "Normally this only occurs under load when records arrive faster than they can be sent out. "

                  + "However it may be desirable to reduce the number of requests even under light load and benefit from bulk indexing. "

                  + "This setting helps accomplishes that - rather than immediately sending out a record, "

                  + "This setting helps accomplish that - when a pending batch is not full, rather than immediately sending it out "

                  + "the task will wait up to the given delay to allow other records to be added so that they can be batched into a single request.",

                  group, ++order, Width.SHORT, "Linger (ms)")

          .define(FLUSH_TIMEOUT_MS_CONFIG, Type.LONG, 10000L, Importance.LOW,

                  "The timeout in milliseconds when flushing records to Elasticsearch.",

                  "The timeout in milliseconds to use for periodic flushing, "

                  + "and when waiting for buffer space to be made available by completed requests as records are added. "

                  + "If this timeout is exceeded the task will fail.",

                  group, ++order, Width.SHORT, "Flush Timeout (ms)")

          .define(MAX_RETRIES_CONFIG, Type.INT, 5, Importance.LOW,

                  "The maximum number of retries that are allowed.",

                  "The maximum number of retries that are allowed for failed indexing requests. "

                  + "If the retry attempts are exhausted the task will fail.",

                  group, ++order, Width.SHORT, "Max Retries")

          .define(RETRY_BACKOFF_MS_CONFIG, Type.LONG, 100L, Importance.LOW,

                  "How long to wait in milliseconds, before attempting to retry a failed batch. This avoids retrying requests in a tight loop under certain failure scenarios.",

                  "How long to wait in milliseconds before attempting to retry a failed indexing request. "

                  + "This avoids retrying in a tight loop under failure scenarios.",

                  group, ++order, Width.SHORT, "Retry Backoff (ms)");

    }