postgres

Commit Graph

Author	SHA1	Message	Date
Andres Freund	32af96b2b1	JIT tuple deforming in LLVM JIT provider. Performing JIT compilation for deforming gains performance benefits over unJITed deforming from compile-time knowledge of the tuple descriptor. Fixed column widths, NOT NULLness, etc can be taken advantage of. Right now the JITed deforming is only used when deforming tuples as part of expression evaluation (and obviously only if the descriptor is known). It's likely to be beneficial in other cases, too. By default tuple deforming is JITed whenever an expression is JIT compiled. There's a separate boolean GUC controlling it, but that's expected to be primarily useful for development and benchmarking. Docs will follow in a later commit containing docs for the whole JIT feature. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de	8 years ago
Andres Freund	2111a48a0c	Adapt expression JIT to stdbool.h introduction. The LLVM JIT provider uses clang to synchronize types between normal C code and runtime generated code. Clang represents stdbool.h style booleans in return values & parameters differently from booleans stored in variables. Thus the expression compilation code from `2a0faed9d` needs to be adapted to `9a95a77d9`. Instead of hardcoding i8 as the type for booleans (which already was wrong on some edge case platforms!), use postgres' notion of a boolean as used for storage and for parameters. Per buildfarm animal xenodermus. Author: Andres Freund	8 years ago
Andres Freund	2a0faed9d7	Add expression compilation support to LLVM JIT provider. In addition to the interpretation of expressions (which back evaluation of WHERE clauses, target list projection, aggregates transition values etc) support compiling expressions to native code, using the infrastructure added in earlier commits. To avoid duplicating a lot of code, only support emitting code for cases that are likely to be performance critical. For expression steps that aren't deemed that, use the existing interpreter. The generated code isn't great - some architectural changes are required to address that. But this already yields a significant speedup for some analytics queries, particularly with WHERE clauses filtering a lot, or computing multiple aggregates. Author: Andres Freund Tested-By: Thomas Munro Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de Disable JITing for VALUES() nodes. VALUES() nodes are only ever executed once. This is primarily helpful for debugging, when forcing JITing even for cheap queries. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de	8 years ago
Andres Freund	fb46ac26fe	Expand list of synchronized types and functions in LLVM JIT provider. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de	8 years ago
Andres Freund	250bca7fc1	Debugging and profiling support for LLVM JIT provider. This currently requires patches to the LLVM codebase to be effective (submitted upstream), the GUCs are available without those patches however. Author: Andres Freund Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de	8 years ago
Andres Freund	b96d550eb0	Support for optimizing and emitting code in LLVM JIT provider. This commit introduces the ability to actually generate code using LLVM. In particular, this adds: - Ability to emit code both in heavily optimized and largely unoptimized fashion - Batching facility to allow functions to be defined in small increments, but optimized and emitted in executable form in larger batches (for performance and memory efficiency) - Type and function declaration synchronization between runtime generated code and normal postgres code. This is critical to be able to access struct fields etc. - Developer oriented jit_dump_bitcode GUC, for inspecting / debugging the generated code. - per JitContext statistics of number of functions, time spent generating code, optimizing, and emitting it. This will later be employed for EXPLAIN support. This commit doesn't yet contain any code actually generating functions. That'll follow in later commits. Documentation for GUCs added, and for JIT in general, will be added in later commits. Author: Andres Freund, with contributions by Pierre Ducroquet Testing-By: Thomas Munro, Peter Eisentraut Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de	8 years ago
Andres Freund	432bb9e04d	Basic JIT provider and error handling infrastructure. This commit introduces: 1) JIT provider abstraction, which allows JIT functionality to be implemented in separate shared libraries. That's desirable because it allows to install JIT support as a separate package, and because it allows experimentation with different forms of JITing. 2) JITContexts which can be, using functions introduced in follow up commits, used to emit JITed functions, and have them be cleaned up on error. 3) The outline of a LLVM JIT provider, which will be fleshed out in subsequent commits. Documentation for GUCs added, and for JIT in general, will be added in later commits. Author: Andres Freund, with architectural input from Jeff Davis Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de	8 years ago

7 Commits (32af96b2b118cd204ca809d7c48c7f8ea7f879cf)