Threaddepth Channel Option

Triggering new jobs
The  channel option tells the  Job Controller when to start a new channel "job" to handle messages: for multithreaded channels, when to start a new thread (if the process is allowed to have more threads) or failing that a new process (if more processes are allowed); for single threaded channels, when to start a new process (if more processes are allowed).

For multithreaded channels, the  channel option controls how many messages are handled in any one thread before the channel will consider starting to use another thread.

In particular, the MTA&#x27;s SMTP client (for channels not marked with the   channel option) sorts outgoing messages to different destinations to different threads. The  channel option may be used to instruct the MTA&#x27;s multithreaded SMTP client to handle only the specified number of messages in any one thread, using additional threads even for messages all to the same destination (hence normally all handled in one thread). The value specified must be greater than 1 and less than 10000. The default as of MS 6.0 is. (This is a change from previous versions, in which the default was 128.)

Use of  may be of particular interest for achieving multithreading with   on a TCP/IP channel - a TCP/IP channel  that connects to a single specific SMTP server - when the SMTP server to which the channel connects can handle multiple simultaneous connections.

Similarly, the  option affects operation of the multithreaded   channel.

For single threaded channels, such as the conversion,  process, and reprocess channels,  the   channel option controls how many messages are handled in a single process; more messages cause the  Job Controller to create another process  (up to the   channel option setting for the  channel and the    Job Controller option value for the    in which the channel runs) to  process the messages.

See also:
 * Job Controller
 * maxjobs Option
 * job_limit Option
 * pool Option
 * ims-ms channels
 * Conversion channel
 * Process and reprocess channels
 * TCPIP channels
 * daemon Option
 * TCPIP connections and DNS lookups channel options
 * Processing control and job submission channel options
 * Channel options