- Legacy puts are now executing asynchronously.
- Memory cache now merges partial cache records.
- Memory cache is used to store data temporarily while it is being written by an async put.
- Expanded the deprecation of persisted boot/memory caches, which no longer offer the performance benefit that they used to.
- Fixed the pak file cache to skip data with a compressed size of over 2 GiB.
#jira UE-141307
#preflight 620d85f93609e19371510fb1
#lockdown Aurel.Cordonnier
#rb Zousar.Shaker
#rnx
#ROBOMERGE-OWNER: Devin.Doucette
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-COMMAND: _robomerge UE5-Main
#ROBOMERGE-SOURCE: CL 19076205 in //UE5/Release-5.0/... via CL 19094550
#ROBOMERGE-BOT: UE5 (Release-Engine-Staging -> Main) (v921-19075845)
[CL 19095974 by devin doucette in ue5-main branch]
- FileSystem, Http, Pak, S3 use the ValueWithLegacyFallback mode by default, which cause them to fall back to searching for uncompressed data if compressed data is not found.
- FileSystem has been fixed to store up to 1 MiB of compressed data inline with the value package rather than separately in content-addressable storage.
- Pak has been optimized to have GetChunks only load the required region of the requested value, rather than the whole value.
- Pak has been changed to stop storing data inline in the record package, since it will end up in the same file anyway when stored separately.
- Pak will upgrade the compressor and compression level when a compressed pak file is requested. Default cache compression uses Oodle Mermaid VeryFast and will upgrade to Oodle Kraken Optimal2.
- Zen does not have compression enabled by default, pending deployment of a new version that stores compressed values to Horde Storage.
- Added a missing request barrier when saving uncompressed data as compressed.
Example reduction in file system cache size when cooking for Windows:
- CitySample dropped from 66.5 GiB to 21.8 GiB.
- Lyra dropped from 2.54 GiB to 672 MiB.
- ShooterGame dropped from 1.21 GiB to 380 MiB.
Example reduction in compressed pak file cache size when cooking for Windows:
- CitySample dropped from 22.3 GiB to 18.5 GiB.
- Lyra dropped from 691 MiB to 543 MiB.
- ShooterGame dropped from 387 MiB to 313 MiB.
#jira UE-134381
#preflight 620a703f583261b0a658e043, 620a6fb2803d9066e6805310, 620a733117632e948459b6af
#lockdown Aurel.Cordonnier
#rb Zousar.Shaker
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18983671 in //UE5/Release-5.0/... via CL 18983890 via CL 18984096
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v917-18934589)
[CL 18984126 by devin doucette in ue5-main branch]
Includes an optimization to avoid an extra copy of data loaded from the cache.
#jira UE-103039
#preflight 6205f379b84973a2bb76d942
#lockdown Aurel.Cordonnier
#rb Zousar.Shaker
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18954059 in //UE5/Release-5.0/... via CL 18954686 via CL 18955089
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v917-18934589)
[CL 18955195 by devin doucette in ue5-main branch]
The cache stores can individually control their "legacy mode" now, which offers a choice of ValueOnly, ValueWithLegacyFallback, LegacyOnly.
- Using ValueOnly will forward every legacy request through the Value API, which compresses values by default and supports values larger than 2 GiB.
- Using ValueWithLegacyFallback behaves like ValueOnly, but misses from GetValue are forwarded to GetCachedData, and stored with PutValue if found.
- Using LegacyOnly will forward every legacy request through the Legacy API.
FLegacyCacheValue uses shared state to ensure that each value is compressed or decompressed at most once.
#jira UE-134381
#preflight 62054b430c64e1822f41231b
#lockdown Mark.Lintott
#rb Zousar.Shaker
#rnx
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18940270 in //UE5/Release-5.0/... via CL 18941016 via CL 18941392
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v917-18934589)
[CL 18941401 by devin doucette in ue5-main branch]
- FCacheRecordPolicyBuilder now disallows adding value policies with flags that only make sense for records.
- FCacheRecordPolicyBuilder now disallows adding multiple value policies for the same value.
- FCacheRecordPolicyBuilder now skips addition of value policies that match the default policy.
#rb Matt.Peters
#rnx
#preflight 61f471cc6b5aea38e5c64cb6
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18782116 in //UE5/Release-5.0/... via CL 18782123 via CL 18782168
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v903-18687472)
[CL 18782178 by devin doucette in ue5-main branch]
The DDC thread pool is a temporary workaround for issues with high-latency cache accesses happening on regular worker thread, which are reduced in number in 5.0 compared to 4.27. Moving it to be private within DDC will keep it easy to remove once the high-latency caches are accessed through an async API.
#rb Zousar.Shaker
#rnx
#preflight 61e5b194873f2ea48f3e0b02
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18634975 in //UE5/Release-5.0/... via CL 18634980 via CL 18634997
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v899-18417669)
[CL 18637555 by devin doucette in ue5-main branch]
This API adds a little bit of overhead but, in exchange:
- Offers a path to migrate to the new Value API.
- Offers a path to provide compression while falling back to the previous format.
- Offers a path to backends batching requests without consuming a worker thread.
- Avoids copying the value multiple times during async puts.
#rb Zousar.Shaker
#rnx
#preflight 61e0a32fed50181feb57c5d6
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18607028 in //UE5/Release-5.0/... via CL 18607056 via CL 18607101
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v899-18417669)
[CL 18607126 by devin doucette in ue5-main branch]
The new API is only implemented for the file system cache store for now. Support for the other cache stores will follow.
#rb Zousar.Shaker
#rnx
#preflight 61d93dd9411c1403a3ee8758
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18561274 in //UE5/Release-5.0/... via CL 18561311
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v899-18417669)
[CL 18561332 by devin doucette in ue5-release-engine-test branch]
A payload was conceptually a value with an ID. That has been formalized by removing the ID from the payload and having separate FValue and FValueId types. This separation cleans up the API in a few areas, and provides a more natural path to providing a basic key/value API.
#rb Zousar.Shaker
#rnx
#preflight 61d704c04c252480ca284d61
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18531844 in //UE5/Release-5.0/... via CL 18531856
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v899-18417669)
[CL 18531864 by devin doucette in ue5-release-engine-test branch]
Stats from the root node must be a superset of stats from the rest of the nodes. The key length limiter is always the root node at present, and has been updated to include stats for the structured cache.
#rb Zousar.Shaker
#rnx
#preflight 61d318cc932a02483cb29797
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18501391 in //UE5/Release-5.0/... via CL 18501397
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v899-18417669)
[CL 18501400 by devin doucette in ue5-release-engine-test branch]
SanitizeCacheKey and ValidateCacheKey should check the same condition
#rb devin.doucette, danny.couture
#ROBOMERGE-AUTHOR: charles.bloom
#ROBOMERGE-SOURCE: CL 18455963 in //UE5/Release-5.0/... via CL 18455975
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v898-18417669)
[CL 18455987 by charles bloom in ue5-release-engine-test branch]
Requests to Put and Get now specify the policy independently for each record or key, but the implementations have not yet been updated to take this into account.
The existing Put and Get API has been maintained temporarily to allow the conversion to happen separately, and will be removed after callers have been converted to use the new API.
#rb Zousar.Shaker
#rnx
#preflight 61b2e550ee0de9822e2e84dc
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18443052 in //UE5/Release-5.0/... via CL 18445037
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v897-18405271)
[CL 18445201 by devin doucette in ue5-release-engine-test branch]
- Implemented only for the structured cache initially.
- Records are stored as compact binary packages with payloads stored within the record if small enough.
- Records are stored in Records/{Bucket}/{01}/{23}/{456789abcdef0123456789abcdef01234567} based on the hash in the cache key.
- Content that exceeds the size allowed for storage within the record is stored in Content/{01}/{23}/{456789abcdef0123456789abcdef01234567} based on the hash of the content.
- Both records and content are written to disk with their hash as a suffix, and are always checked on load.
- Maximum size of compressed data stored in the package can be configured by MaxRecordSizeKB and MaxValueSizeKB.
- Maintenance of the cache, to delete unused files, has been rewritten and can now scan ~175k files/second on modern hardware, though is limited to 10k files/second in the config to avoid adding too much overhead.
#rb Zousar.Shaker
#preflight 618b75c14a0c609a29204032
#preflight 618bfb5ec717ba4e929b7ac0
#ROBOMERGE-AUTHOR: devin.doucette
#ROBOMERGE-SOURCE: CL 18133085 in //UE5/Release-5.0/... via CL 18133356
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v889-18060218)
#ROBOMERGE[STARSHIP]: UE5-Main
[CL 18133430 by devin doucette in ue5-release-engine-test branch]
This represents UE4/Main @18073326, Release-5.0 @18081140 and Dev-PerfTest @18045971
[CL 18081471 by aurel cordonnier in ue5-release-engine-test branch]
