Buffer cache management to prevent deadlocks

A computer program product in one or more tangible computer-readable media of computer code, comprising functional descriptive material that, when executed by a computer, causes the computer to perform actions of:

• determining that a thread executing in the computer requires an allocation of one or more input/output buffers in a buffer cache residing in memory of the computer;
• determining if performing the allocation would result in the buffer cache having a number of free buffers that is less than a pre-determined threshold;
• in response to a determination that performing the allocation would result in the buffer cache having a number of free buffers that is less than the pre-determined threshold, increasing a total size of the buffer cache;
• determining if performing the allocation would result in the buffer cache having a number of free buffers that is less than a minimum number of buffers needed to perform the action of increasing the total size of the buffer cache;
• in response to a determination that performing the allocation would result in the buffer cache having a number of free buffers that is less than the minimum number of buffers needed to perform the action of increasing the total size of the buffer cache, blocking the thread until the allocation can be performed without the buffer cache having fewer than the minimum number of buffers needed to perform the action of increasing the total size of the buffer cache;
• and
• in response to a determination that performing the allocation would not result in the buffer cache having a number of free buffers that is less than the minimum number of buffers needed to perform the action of increasing the total size of the buffer cache, performing the allocation.

A data processing system comprising:

• at least one processor;
• data storage accessible to the at least one processor;
• and
• a set of instructions in the data storage, wherein the at least one processor executes the set of instructions to perform actions of:
• determining that a thread executing in the data processing system requires an allocation of one or more input/output buffers in a buffer cache residing in the data storage;
• determining if performing the allocation would result in the buffer cache having a number of free buffers that is less than a pre-determined threshold;
• in response to a determination that performing the allocation would result in the buffer cache having a number of free buffers that is less than the pre-determined threshold, increasing a total size of the buffer cache;
• determining if performing the allocation would result in the buffer cache having a number of free buffers that is less than a minimum number of buffers needed to perform the action of increasing the total size of the buffer cache;
• in response to a determination that performing the allocation would result in the buffer cache having a number of free buffers that is less than the minimum number of buffers needed to perform the action of increasing the total size of the buffer cache, blocking the thread until the allocation can be performed without the buffer cache having fewer than the minimum number of buffers needed to perform the action of increasing the total size of the buffer cache;
• and
• in response to a determination that performing the allocation would not result in the buffer cache having a number of free buffers that is less than the minimum number of buffers needed to perform the action of increasing the total size of the buffer cache, performing the allocation.