Chkdsk scan speed is being throttled to reduce impact on system and application performance. Given the number of files and ...

Chkdsk scan speed is being throttled to reduce impact on system and application 
performance.  Given the number of files and directories on the drive, Windows 
can scan the drive more efficiently if it has more memory available.
To enable Chkdsk to use all available system memory and increase scan 
performance, please use the /perf switch.