ConcurrentFlotsamAssetCache.ini.example

; config-include/ConcurrentFlotsamAssetCache.ini
[AssetCache]
    ; Enable or disable the on-disk cache. If false, nothing is written to disk.
    ; Default: true
    FileCacheEnabled = true

    ; Root directory for cached asset files (absolute or relative to OpenSim.exe).
    ; Default: c_assetcache
    CacheDirectory = c_assetcache

    ; Enable or disable the in-memory cache (fastest tier).
    ; Default: false
    MemoryCacheEnabled = false

    ; Memory cache timeout in hours (float). Internally converted to seconds.
    ; Small values reduce RAM; larger values may improve hit rate.
    ; Default: 0.016 (≈ 57.6 seconds)
    MemoryCacheTimeout = 0.016

    ; Enable negative cache to short-circuit repeated misses for a short time.
    ; Default: true
    NegativeCacheEnabled = true

    ; Negative cache TTL in seconds.
    ; Default: 120
    NegativeCacheTimeout = 120

    ; Optional maximum size for the negative cache to control memory usage.
    ; When exceeded, a batch of old/expired entries is pruned.
    ; Default: 100000
    NegativeCacheMaxEntries = 100000

    ; How many entries to remove when pruning the negative cache.
    ; Default: 5000
    NegativeCachePruneBatch = 5000

    ; Update file LastAccessTime on cache hits (touch). Helps expiration logic,
    ; but can add IO. Internally throttled.
    ; Default: false (effective, because it is masked by FileCacheEnabled)
    UpdateFileTimeOnCacheHit = false

    ; Log verbosity for this module (0=minimal, 1=info, 2=verbose warnings).
    ; Default: 0
    LogLevel = 0

    ; Show hit-rate statistics every N requests (0 disables).
    ; Default: 100
    HitRateDisplay = 100

    ; Sampling size used to estimate alive WeakReference entries in hit report.
    ; Larger values increase accuracy but also CPU work during reporting.
    ; Default: 2000 (minimum enforced: 100)
    HitReportWeakRefSampleTarget = 2000

    ; Expiration for on-disk files since last access (in hours).
    ; Files older than now - FileCacheTimeout are eligible for removal.
    ; Default: 48
    FileCacheTimeout = 48

    ; How often (in hours) the background cleaner runs.
    ; Default: 1.0
    FileCleanupTimer = 1.0

    ; Directory sharding – number of tier levels (1..3).
    ; Default: 1
    CacheDirectoryTiers = 1

    ; Directory sharding – characters per tier segment (1..4).
    ; Default: 3
    CacheDirectoryTierLength = 3

    ; Warn if a single cache directory contains more than this many entries.
    ; Helps tune sharding/expiration.
    ; Default: 30000
    CacheWarnAt = 30000

    ; Safer replace behavior: keep a temporary backup when replacing files (Windows/NTFS).
    ; Backup files (.bak) are placed beside the target file.
    ; Default: false
    FileReplaceKeepBackup = false

    ; Allow overwrite moves when supported by the platform/runtime (NET6+).
    ; Default: true
    FileMoveAllowOverwrite = true

    ; Cleanup of stale .bak files (from interrupted replacements).
    ; If enabled, the background cleaner removes old .bak files.
    ; Default: true
    BakCleanupEnabled = true

    ; Max age (in hours) for .bak files before they are removed by the cleaner.
    ; Default: 24 (range enforced: 1 .. 168)
    BakCleanupMaxAgeHours = 24

    ; Deserialization safety limits (protect against oversized/corrupt cache files):
    ; Maximum UTF-8 string length per field (bytes). Floors/ceilings enforced internally.
    ; Default: 262144 (256 KB)  [floor: 32768, ceiling: 2097152]
    DeserializeMaxStringLenBytes = 262144

    ; Maximum asset data size (MB). Floors/ceilings enforced internally.
    ; Default: 64  [floor: 8, ceiling: 512]
    DeserializeMaxDataLenMB = 64

    ; Backoff when a file is being written by another thread (thundering herd control):
    ; Number of retry attempts.
    ; Default: 3  [0..10]
    BackoffAttempts = 3

    ; Initial backoff delay in milliseconds (exponential growth per attempt).
    ; Default: 5  [0..500]
    BackoffInitialMs = 5

    ; Maximum backoff delay per attempt in milliseconds (cap).
    ; Default: 40  [>= BackoffInitialMs, <= 2000]
    BackoffMaxMs = 40
    
    ; File writer concurrency (number of threads).
    ; Default: 1 (recommended) Max: 4 (can be dangerous for the disk) 
    FileWriterConcurrencyWorker = 1