Memory Pre-Allocation For Cleanup and Rollback Operations
A plurality of operations are executed using first memory (e.g., heap memory, etc.) in a data storage application. During execution, it is determined that one of the operations cannot be executed due to a lack of available first memory. In response, an emergency allocator assigns pre-allocated emergency memory that is separate and distinct from the first memory to the determined operation. The operation can then be completed using this pre-allocated emergency memory. Related apparatus, systems, techniques and articles are also described.
1 . A method comprising:
executing a plurality of operations using first memory in a data storage application;
determining that one of the operations cannot be executed due to a lack of available first memory;
assigning, by an emergency allocator, pre-allocated emergency memory to the determined operation, the pre-allocated emergency memory being separate and distinct from the first memory; and
completing the determined operation using the pre-allocated emergency memory.
2 . A method as in claim 1 , wherein the operations comprise rollback operations.
3 . A method as in claim 1 , wherein the operations comprise cleanup operations.
4 . A method as in claim 1 , wherein it is determined that one of the operations cannot be executed due to a lack of available first memory based on a thrown exception.
5 . A method as in claim 1 , wherein each operation is performed by a separate thread, and wherein the pre-allocated emergency memory is assigned to the corresponding thread for the determined operation.
6 . A method as in claim 5 , wherein the emergency allocator only assigns the pre-allocated emergency memory to one thread at a time.
7 . A method as in claim 1 , wherein the data storage application uses shadow paging to write a transactionally-consistent savepoint.
8 . A method as in claim 7 , wherein a data backup corresponding to the plurality of executed transactions comprises a copy of all data pages contained with a particular savepoint.
9 . A method as in claim 1 , wherein the data storage application comprises an in-memory database.
10 . A method as in claim 1 , wherein the first memory is heap memory.
11 . A method as in claim 1 , further comprising:
freeing the pre-allocated emergency memory and releasing the emergency allocator after completion of the determined operation.
12 . A non-transitory computer program product storing instructions, which when executed by at least one data processor, result in operations comprising:
executing a plurality of operations using first memory in a data storage application;
determining that one of the operations cannot be executed due to a lack of available first memory;
assigning, by an emergency allocator, pre-allocated emergency memory to the determined operation, the pre-allocated emergency memory being separate and distinct from the first memory; and
completing the determined operation using the pre-allocated emergency memory.
13 . A computer program product as in claim 12 , wherein the operations comprise rollback operations and cleanup operations.
14 . A computer program product as in claim 12 , wherein it is determined that one of the operations cannot be executed due to a lack of available first memory based on a thrown exception.
15 . A computer program product as in claim 12 , wherein each operation is performed by a separate thread, and wherein the pre-allocated emergency memory is assigned to the corresponding thread for the determined operation.
16 . A computer program product as in claim 15 , wherein the emergency allocator only assigns the pre-allocated emergency memory to one thread at a time.
17 . A computer program product as in claim 12 , wherein the data storage application uses shadow paging to write a transactionally-consistent savepoint, wherein a data backup corresponding to the plurality of executed transactions comprises a copy of all data pages contained with a particular savepoint.
18 . A computer program product as in claim 12 , wherein the data storage application comprises an in-memory database.
19 . A computer program product as in claim 12 , wherein the operations further comprise:
freeing the pre-allocated emergency memory and releasing the emergency allocator after completion of the determined operation.
20 . A system comprising:
a data storage application comprising an in-memory database;
one or more data processors; and
memory storing instructions, which, when executed by at least one data processor, result in operations comprising:
executing a plurality of operations using first memory in the data storage application;
determining that one of the operations cannot be executed due to a lack of available first memory;
assigning, by an emergency allocator, pre-allocated emergency memory to the determined operation, the pre-allocated emergency memory being separate and distinct from the first memory; and
completing the determined operation using the pre-allocated emergency memory.