Pointers for Eliminating Heaps of Memory
summary
Covers concrete changes in Ruby 2.6: uses Malloc Stack Logging on macOS to find where mallocs come from, patches the loaded_features cache to share and eliminate string allocations (about 50% fewer string allocations for one example) and replaces the instruction-sequence mark array with Direct ISeq Marking, cutting boot-time array allocations from ~35k to ~8.5k (≈34% fewer objects) and reducing overall process memory ~4–6% depending on how many files an app loads.
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chapters (22)
- 0:00Start
- 7:36Malloc Stack Logging
- 8:23Dump Malloc Logs
- 8:49Log File Size
- 8:59File Contents
- 9:20Reconciling Live Memory
- 14:22Cache Structure
- 14:41Generation Algorithm
- 14:56Key Generation
- 18:27Output
- 18:58Malloc Logging
- 21:42Stack VM
- 22:59Processing Phases
- 25:43Optimization Pass
- 26:13Byte Code Translation
- 27:55Hello World
- 29:16VM Implementation
- 30:48Object Allocations
- 32:18ISeq Layout
- 37:21Basic Rails App
- 37:53Process Memory: -6%
- 38:23Actual Code
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