For restartable downloads, specifies the maximum amount of data that may need to be resent after a communications failure.

Syntax

drs=number[ K ]; ...

Remarks

The DownloadReadSize option is only useful when doing restartable downloads.

The download read size is specified in units of bytes. Use the suffix k to optionally specify units of kilobytes.

Dbmlsync reads the download in chunks. The DownloadReadSize defines the size of these chunks. When a communication error occurs, dbmlsync loses the entire chunk that was being processed. Depending on when the error occurs, the number of bytes lost range between 0 and the DownloadReadSize -1. So for example, if the DownloadReadSize is 100 bytes and an error occurs after reading 497 bytes, the last 97 bytes read are lost. Bytes that are lost in this way are resent when the download is restarted.

In general, larger DownloadReadSize values result in better performance on successful synchronizations but result in more data being resent when an error occurs.

The typical use of this option is to reduce the default size when communication is unreliable.

The default is 32767. If you set this option to a value larger than 32767, the value 32767 is used.

This option has a short form and long form: you can use drs or DownloadReadSize.

You can also store extended options in the database. For more information about dbmlsync extended options, see Introduction to dbmlsync extended options.

See also

• -drs option
• Resuming failed downloads
• ContinueDownload (cd) extended option
• sp_hook_dbmlsync_end
• -dc option

Example

The following dbmlsync command line illustrates how you can set this option when you start dbmlsync:

dbmlsync -e "drs=100"

The following SQL statement illustrates how you can store this option in the database:

CREATE SYNCHRONIZATION SUBSCRIPTION
   TO sales_publication
   FOR ml_user1
   OPTION drs='100';