#rb na
#ROBOMERGE-OWNER: robert.manuszewski
#ROBOMERGE-AUTHOR: andrew.grant
#ROBOMERGE-SOURCE: CL 7119039 in //UE4/Main/...
#ROBOMERGE-BOT: CORE (Main -> Dev-Core) (v367-6836689)
[CL 7138723 by andrew grant in Dev-Core branch]
Live++ reads object files at startup for game modules, and assigns unique ids to each compiland (used to disambiguate static variables). When compiling the patch, these compilands are modified to reference a unique id for the unity blob, causing the variables to be reconstructed.
Solution is to generate a JSON file to each output directory containing object files containing the mapping, and to use that to assign compiland ids at startup.
#rb none
#jira UE-74036
#ROBOMERGE-OWNER: robert.manuszewski
#ROBOMERGE-AUTHOR: ben.marsh
#ROBOMERGE-SOURCE: CL 6455253 in //UE4/Release-4.22/... via CL 6455273
#ROBOMERGE-BOT: CORE (Main -> Dev-Core)
[CL 6476049 by ben marsh in Dev-Core branch]
Live++ reads object files at startup for game modules, and assigns unique ids to each compiland (used to disambiguate static variables). When compiling the patch, these compilands are modified to reference a unique id for the unity blob, causing the variables to be reconstructed.
Solution is to generate a JSON file to each output directory containing object files containing the mapping, and to use that to assign compiland ids at startup.
#rb none
#jira UE-74036
#ROBOMERGE-SOURCE: CL 6455253 in //UE4/Release-4.22/...
#ROBOMERGE-BOT: RELEASE (Release-4.22 -> Main)
[CL 6455273 by ben marsh in Main branch]
#rb none
#jira UE-73075
#ROBOMERGE-SOURCE: CL 6017285 in //UE4/Release-4.22/...
#ROBOMERGE-BOT: RELEASE (Release-4.22 -> Main)
[CL 6017289 by ben marsh in Main branch]
#jira
#rb none
#ROBOMERGE-OWNER: ben.marsh
#ROBOMERGE-AUTHOR: ben.marsh
#ROBOMERGE-SOURCE: CL 5993252 via CL 5993257 via CL 5995286
[CL 5995562 by ben marsh in Main branch]
#rb none
#jira UE-72524
#ROBOMERGE-SOURCE: CL 5988868 in //UE4/Release-4.22/...
#ROBOMERGE-BOT: RELEASE (Release-4.22 -> Main)
[CL 5988908 by ben marsh in Main branch]
Encoding improvements
* New hash table implementation
--- Move away from 16-bit hashes since we need more than 64k buckets to hold 2M entries efficiently
--- Change to CityHash64, which is faster and stronger
--- Remove hardcoded max limit
* NAME_INDEX changed from contigouos int to monotonically increasing int
--- Opens up for future deduplication schemes that are better than number suffix dedup.
--- Saves some memory since we don't need to maintain a contiguous array
--- Typed up to cause compile errors when used as integer directly
* Avoid touching data repeatedly, normal path only does single hash of data
* New constructor that allows supplying string length up front
* Avoid dynamic allocations in string conversions >= 128 characters
* Avoid extra copying when splitting numbers
* More efficient IsPureAnsi check
* Only do one global lazy initialization call instead of multiple
* Switch to faster RW locks
* Switch from single lock to sharded hash map with separate locks
* Memory optimizations that reduces per entry overhead: 4 bytes slots, 2 byte headers and don't store null terminator
Improved API & documentation
* Document that IsValid() rarely makes sense
* Hide global state such as GetNames()
* Reduce amount of implementation details visible in header
* NameTypes.h size down by ~1/3 while adding documentation, stronger type safety and new APIs
Future possibilities
* Memory savings: Removing public NAME_INDEX and global FName array allows using the 32-bit FNameEntryId for arbitrary deduplication schemes. This can save both actual stored strings memory by deduplication and half the size of FName instances from 8B to 4B in shipping / test configs by removing the number part.
* Implementation can be tweaked further, for instance could persist 32-bit slot index hash inside slot to increase encoding performance in development / debug at the cost of memory.
Perf & mem results for internal project:
* Editor startup wall time: 12% speedup, 22.0s -> 19.5s
--- Warm disk and asset registry cache
--- Some gains from nametable serialization improvements
--- Some of these gains might be from orthogonal asset discovery optimizations
* Win64 Test Client memory usage with ~400k names: 30.3Mb -> 22.2Mb
#rb steve.robb, pj.kack
#jira UE-59973
[CL 5774657 by Johan Torp in Dev-Core branch]
Now stores the linker environment block in the live coding manifest, and adds it to the cache before executing the linker.
#rb none
#jira UE-72324
#ROBOMERGE-OWNER: robert.manuszewski
#ROBOMERGE-AUTHOR: ben.marsh
#ROBOMERGE-SOURCE: CL 5740602 in //UE4/Release-4.22/... via CL 5740765
#ROBOMERGE-BOT: CORE (Main -> Dev-Core)
[CL 5743844 by ben marsh in Dev-Core branch]
Now stores the linker environment block in the live coding manifest, and adds it to the cache before executing the linker.
#rb none
#jira UE-72324
#ROBOMERGE-OWNER: ben.marsh
#ROBOMERGE-AUTHOR: ben.marsh
#ROBOMERGE-SOURCE: CL 5740602 in //UE4/Release-4.22/...
#ROBOMERGE-BOT: RELEASE (Release-4.22 -> Main)
[CL 5740765 by ben marsh in Main branch]
