Dynamic block write cache pass-through mode

A computer system, comprising:

• a processor system;
• and
• a computer storage medium that stores computer-executable instructions that are executable by the processor system to at least:
• determine that a condition has been met for transitioning write input/output (I/O) requests for a consumer from a write-caching mode to a pass-through mode;
• de-stage one or more logs for the consumer from a write cache to a backing store, each log corresponding to a pending write I/O operation by the consumer;
• route a first new write I/O request to the write cache after determining that the condition has been met;
• determine that no log for the consumer remains in the write cache for de-staging to the backing store;
• and
• initiate the pass-through mode after determining that no log for the consumer remains in the write cache for de-staging to the backing store, including routing a second new write I/O request to the backing store rather than routing the second new write I/O request to the write cache.

A computer storage medium that stores computer-executable instructions that are executable by a processor system to at least:

• determine that a condition has been met for transitioning write input/output (I/O) requests for a consumer from a write-caching mode to a pass-through mode;
• de-stage one or more logs for the consumer from a write cache to a backing store, each log corresponding to a pending write I/O operation by the consumer;
• route a first new write I/O request to the write cache after determining that the condition has been met, including introducing latency into the first new write I/O request based on,
• a first rate of de-staging the one or more logs for the consumer from the write cache to the backing store, or
• a second rate of write I/O requests received after identifying the condition for transitioning write I/O requests for the consumer;
• determine that no log for the consumer remains in the write cache for de-staging to the backing store;
• and
• initiate the pass-through mode after determining that no log for the consumer remains in the write cache for de-staging to the backing store, including routing a second new write I/O request to the backing store rather than routing the second new write I/O request to the write cache.