What are the acceptable values or warning thresholds for this performance monitor?

"log generation checkpoint depth"

The following applies to 2007, does an article exist for 2013?

https://technet.microsoft.com/en-us/library/bb218463(v=exchg.80).aspx

MS increased the checkpoint depth on 2013 compared to 2010. Checkpoint depth target for active and passive copy in 2013 is 100MB. so you can set threshold some what more than 2010. but i couldn't find any recommending value for this perf counter.