<> <> <> <> <> <> DIRECTORY AlpineInternal, AlpineEnvironment USING[PageNumber], FileMap USING[VerifyFilePageMgrHandle, Handle], FilePageMgrLru USING[LruListPlace, SweepItem], FilePageMgrPrivateChunk USING[Chunk, ChunkAllocator, ChunkIsDirty, ChunkType, ListChunkType, InternalFilePageMgrLogicError, RefChunk, Sweeper], FilePageMgrPrivateFile USING[FPMFileObject, FPMFileHandle], Process USING[Detach, MsecToTicks, SetTimeout, Ticks]; FilePageMgrLruImpl: CEDAR MONITOR IMPORTS FileMap, FpmPC: FilePageMgrPrivateChunk, Process EXPORTS AlpineInternal, FilePageMgrLru = BEGIN OPEN AE: AlpineEnvironment, FpmL: FilePageMgrLru, FpmPF: FilePageMgrPrivateFile; FPMFileObject: PUBLIC TYPE = FpmPF.FPMFileObject; FPMFileHandle: PUBLIC TYPE = FpmPF.FPMFileHandle; Chunk: PUBLIC TYPE = FpmPC.Chunk; RefChunk: PUBLIC TYPE = FpmPC.RefChunk; ListChunkType: TYPE = FpmPC.ListChunkType; lruList: ARRAY ListChunkType OF RefChunk _ ALL[NIL]; nLruListChunks: ARRAY ListChunkType OF NAT _ ALL[0]; initialLruListChunks: ARRAY ListChunkType OF NAT _ ALL[0]; lruListLimit: NAT; LruListParamsTooSmall: ERROR = CODE; <> AddAsLru: INTERNAL PROCEDURE[refChunk: RefChunk] = BEGIN -- non system fatal errors: none. chunkType: ListChunkType = refChunk.chunkType; refHeaderChunk: RefChunk = lruList[chunkType]; IF ((refChunk.next # NIL) OR (refChunk.prev # NIL)) THEN ERROR FpmPC.InternalFilePageMgrLogicError; nLruListChunks[chunkType] _ nLruListChunks[chunkType] + 1; refHeaderChunk.next.prev _ refChunk; refChunk.next _ refHeaderChunk.next; refChunk.prev _ refHeaderChunk; refHeaderChunk.next _ refChunk; END; AddAsMru: INTERNAL PROCEDURE[refChunk: RefChunk] = BEGIN -- non system fatal errors: none. chunkType: ListChunkType = refChunk.chunkType; refHeaderChunk: RefChunk = lruList[chunkType]; IF ((refChunk.next # NIL) OR (refChunk.prev # NIL)) THEN ERROR FpmPC.InternalFilePageMgrLogicError; nLruListChunks[chunkType] _ nLruListChunks[chunkType] + 1; refHeaderChunk.prev.next _ refChunk; refChunk.next _ refHeaderChunk; refChunk.prev _ refHeaderChunk.prev; refHeaderChunk.prev _ refChunk; END; Unlink: INTERNAL PROCEDURE[refChunk: RefChunk] = BEGIN -- non system fatal errors: none. chunkType: ListChunkType = refChunk.chunkType; IF (nLruListChunks[chunkType] _ nLruListChunks[chunkType] - 1) < 0 THEN ERROR FpmPC.InternalFilePageMgrLogicError; refChunk.prev.next _ refChunk.next; refChunk.next.prev _ refChunk.prev; refChunk.prev _ NIL; -- for refChunk.next _ NIL; -- debugging. END; UnexpectedHorror: ERROR = CODE; PutMappedChunkOnLruList: PUBLIC ENTRY PROCEDURE[refChunk: RefChunk, lruListPlace: FpmL.LruListPlace] = BEGIN -- non system fatal errors: none. ErrorProc: PROCEDURE RETURNS[fpmFileHandle: FPMFileHandle] = BEGIN ERROR UnexpectedHorror; END; fPMFileHandle: FPMFileHandle _ FileMap.VerifyFilePageMgrHandle[refChunk.fileHandle, ErrorProc]; (IF lruListPlace = mru THEN AddAsMru ELSE AddAsLru)[refChunk]; fPMFileHandle.nLruListChunks _ fPMFileHandle.nLruListChunks + 1; END; PutUnmappedChunkOnLruList: PUBLIC ENTRY PROCEDURE[refChunk: RefChunk] = BEGIN -- non system fatal errors: none. AddAsLru[refChunk]; END; GetOurChunkFromLruList: PUBLIC ENTRY PROCEDURE [refChunk: RefChunk, tellSweeperToHurry: BOOLEAN] = BEGIN -- non system fatal errors: none. ErrorProc: PROCEDURE RETURNS[fpmFileHandle: FPMFileHandle] = BEGIN ERROR UnexpectedHorror; END; fPMFileHandle: FPMFileHandle _ FileMap.VerifyFilePageMgrHandle[refChunk.fileHandle, ErrorProc]; Unlink[refChunk]; fPMFileHandle.nLruListChunks _ fPMFileHandle.nLruListChunks - 1; IF tellSweeperToHurry THEN HurryUpSweeper[refChunk.chunkType]; END; <> NoMoreChunksAvailable: ERROR = CODE; -- all the chunks of a given type are in use when another is requested. GetOtherChunkFromLruList: PUBLIC ENTRY PROCEDURE [chunkType: ListChunkType] RETURNS [mapped: BOOLEAN, refChunk: RefChunk, fileHandle: FileMap.Handle, startFilePageNumber: AE.PageNumber] = BEGIN -- non system fatal errors: none. IF (refChunk _ lruList[chunkType].next) = lruList[chunkType] THEN ERROR NoMoreChunksAvailable; -- fatal. Unlink[refChunk]; IF (mapped _ (refChunk.fileHandle # NIL)) THEN BEGIN AddAsMru[refChunk]; RETURN[mapped, refChunk, refChunk.fileHandle, refChunk.startFilePageNumber]; END; END; RelinkChunkAsLruOnLruList: PUBLIC ENTRY PROCEDURE[refChunk: RefChunk] = BEGIN -- non system fatal errors: none. Unlink[refChunk]; AddAsLru[refChunk]; END; checkDuringNotDebugging: BOOLEAN _ TRUE; UsingTooMuchOfCache: PUBLIC ENTRY PROCEDURE[fPMFileHandle: FPMFileHandle] RETURNS [yes: BOOLEAN] = BEGIN -- non system fatal errors: none. RETURN[(checkDuringNotDebugging) AND (nLruListChunks[normal] # 0) AND (fPMFileHandle.nLruListChunks > lruListLimit)]; END; CheckCacheInCleanState: PUBLIC ENTRY PROCEDURE RETURNS [clean: BOOLEAN] = BEGIN -- non system fatal errors: none. FOR chunkType: ListChunkType IN ListChunkType DO FOR refChunk: RefChunk _ lruList[chunkType].next, refChunk.next UNTIL refChunk = lruList[chunkType] DO IF refChunk.fileHandle # NIL THEN RETURN[FALSE]; ENDLOOP; IF initialLruListChunks[chunkType] # nLruListChunks[chunkType] THEN RETURN[FALSE]; ENDLOOP; RETURN[TRUE]; END; timeToSleepBetweenSweeps: ARRAY ListChunkType OF Process.Ticks _ ALL[Process.MsecToTicks[1000]]; MaxTimeToSleepBetweenSweeps: ARRAY ListChunkType OF Process.Ticks _ ALL[Process.MsecToTicks[1000]]; MinTimeToSleepBetweenSweeps: ARRAY ListChunkType OF Process.Ticks _ ALL[Process.MsecToTicks[100]]; SweepNeeded: ARRAY ListChunkType OF CONDITION _ [normal: [timeout: timeToSleepBetweenSweeps[normal]], log: [timeout: timeToSleepBetweenSweeps[log]], leader: [timeout: timeToSleepBetweenSweeps[leader]]]; hurryUp: ARRAY ListChunkType OF BOOLEAN _ ALL[FALSE]; HurryUpSweeper: INTERNAL PROCEDURE[chunkType: ListChunkType] = BEGIN -- non system fatal errors: none. hurryUp[chunkType] _ TRUE; NOTIFY SweepNeeded[chunkType]; END; WaitToSweep: PUBLIC ENTRY PROCEDURE [oldNeedToHurry: BOOLEAN, chunkType: ListChunkType] RETURNS[needToHurry: BOOLEAN, sweepList: LIST OF FpmL.SweepItem] = BEGIN -- non system fatal errors: none. refChunk: RefChunk; timeToSleepBetweenSweeps[chunkType] _ IF oldNeedToHurry THEN MAX[timeToSleepBetweenSweeps[chunkType]/2, MinTimeToSleepBetweenSweeps[chunkType]] ELSE MIN[(timeToSleepBetweenSweeps[chunkType] + timeToSleepBetweenSweeps[chunkType]), MaxTimeToSleepBetweenSweeps[chunkType]]; hurryUp[chunkType] _ FALSE; TRUSTED BEGIN Process.SetTimeout[@SweepNeeded[chunkType], timeToSleepBetweenSweeps[chunkType]]; END; WAIT SweepNeeded[chunkType]; refChunk _ lruList[chunkType].prev; -- mru. sweepList _ NIL; DO IF refChunk = lruList[chunkType] THEN EXIT; IF ((refChunk.fileHandle # NIL) AND (FpmPC.ChunkIsDirty[refChunk])) THEN sweepList _ CONS[[refChunk.fileHandle, refChunk.startFilePageNumber], sweepList]; refChunk _ refChunk.prev; ENDLOOP; needToHurry _ hurryUp[chunkType]; END; InitializeLruLists: PUBLIC ENTRY PROCEDURE[nChunks: ARRAY ListChunkType OF NAT] = BEGIN -- non system fatal errors: none. IF moduleInitialized THEN ERROR; FOR chunkType: ListChunkType IN ListChunkType DO IF nChunks[chunkType] = 0 THEN RETURN WITH ERROR LruListParamsTooSmall; lruList[chunkType] _ FpmPC.ChunkAllocator[lruHeader, TRUE]; lruList[chunkType].prev _ lruList[chunkType].next _ lruList[chunkType]; THROUGH [0..nChunks[chunkType]) DO AddAsMru[FpmPC.ChunkAllocator[chunkType, TRUE]]; ENDLOOP; initialLruListChunks[chunkType] _ nChunks[chunkType]; ENDLOOP; IF ((checkDuringNotDebugging) AND ((lruListLimit _ nLruListChunks[normal]/10) = 0)) THEN RETURN WITH ERROR LruListParamsTooSmall; FOR chunkType: ListChunkType IN ListChunkType DO TRUSTED BEGIN Process.Detach[FORK FpmPC.Sweeper[chunkType]]; END; ENDLOOP; moduleInitialized _ TRUE; END; <> moduleInitialized: BOOLEAN _ FALSE; END. Edit Log Initial: Kolling: 23-Feb-82 12:34:40: manager of the lru structure for the File Page Manager. Nodified: Hauser: February 20, 1985 3:17:50 pm PST <> <>