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

Syntax

dbmlsync  -drs bytes ...

Remarks

The -drs option specifies a download read size that is only useful when doing restartable downloads.

Dbmlsync reads the download in chunks. The download read size 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 ranges between 0 and the download read size -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 download read size 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.

You can also specify the download read size using the DownloadReadSize extended option.

See also

• DownloadReadSize (drs) extended 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 -drs 100