diff options
Diffstat (limited to 'lib/system/gc_ms.nim')
| -rw-r--r-- | lib/system/gc_ms.nim | 82 |
1 files changed, 31 insertions, 51 deletions
diff --git a/lib/system/gc_ms.nim b/lib/system/gc_ms.nim index eaea76235..246a42870 100644 --- a/lib/system/gc_ms.nim +++ b/lib/system/gc_ms.nim @@ -11,8 +11,9 @@ {.push profiler:off.} const - CycleIncrease = 2 # is a multiplicative increase - InitialCycleThreshold = 4*1024*1024 # X MB because cycle checking is slow + InitialThreshold = 4*1024*1024 # X MB because marking&sweeping is slow + +template mulThreshold(x): expr {.immediate.} = x * 2 when defined(memProfiler): proc nimProfile(requestedSize: int) @@ -31,12 +32,10 @@ type TGlobalMarkerProc = proc () {.nimcall.} TGcStat = object - stackScans: int # number of performed stack scans (for statistics) collections: int # number of performed full collections maxThreshold: int # max threshold that has been set maxStackSize: int # max stack size - maxStackCells: int # max stack cells in ``decStack`` - cycleTableSize: int # max entries in cycle table + freedObjects: int # max entries in cycle table TGcHeap = object # this contains the zero count and # non-zero count table @@ -87,33 +86,24 @@ proc unsureAsgnRef(dest: ppointer, src: pointer) {.inline.} = dest[] = src proc internRefcount(p: pointer): int {.exportc: "getRefcount".} = - result = int(usrToCell(p).refcount) + result = 0 var globalMarkersLen: int - globalMarkers: array[0.. 10_000, TGlobalMarkerProc] + globalMarkers: array[0.. 7_000, TGlobalMarkerProc] -proc nimRegisterGlobalMarker(markerProc: pointer) {.compilerProc.} = - globalMarkers[globalMarkersLen] = cast[TGlobalMarkerProc](markerProc) - inc globalMarkersLen +proc nimRegisterGlobalMarker(markerProc: TGlobalMarkerProc) {.compilerProc.} = + if globalMarkersLen <= high(globalMarkers): + globalMarkers[globalMarkersLen] = markerProc + inc globalMarkersLen + else: + echo "[GC] cannot register global variable; too many global variables" + quit 1 # this that has to equals zero, otherwise we have to round up UnitsPerPage: when BitsPerPage mod (sizeof(int)*8) != 0: {.error: "(BitsPerPage mod BitsPerUnit) should be zero!".} -proc writeCell(msg: CString, c: PCell) = - var kind = -1 - if c.typ != nil: kind = ord(c.typ.kind) - when leakDetector: - c_fprintf(c_stdout, "[GC] %s: %p %d rc=%ld from %s(%ld)\n", - msg, c, kind, c.refcount, c.filename, c.line) - else: - c_fprintf(c_stdout, "[GC] %s: %p %d rc=%ld\n", - msg, c, kind, c.refcount) - -template gcTrace(cell, state: expr): stmt {.immediate.} = - when traceGC: traceCell(cell, state) - # forward declarations: proc collectCT(gch: var TGcHeap) proc IsOnStack*(p: pointer): bool {.noinline.} @@ -133,20 +123,18 @@ proc prepareDealloc(cell: PCell) = (cast[TFinalizer](cell.typ.finalizer))(cellToUsr(cell)) dec(gch.recGcLock) -proc nimGCref(p: pointer) {.compilerProc, inline.} = inc(usrToCell(p).refCount) -proc nimGCunref(p: pointer) {.compilerProc, inline.} = dec(usrToCell(p).refCount) +proc nimGCref(p: pointer) {.compilerProc, inline.} = + # we keep it from being collected by pretending it's not even allocated: + excl(gch.allocated, usrToCell(p)) +proc nimGCunref(p: pointer) {.compilerProc, inline.} = + incl(gch.allocated, usrToCell(p)) proc initGC() = when not defined(useNimRtl): - when traceGC: - for i in low(TCellState)..high(TCellState): Init(states[i]) - gch.cycleThreshold = InitialCycleThreshold - gch.stat.stackScans = 0 + gch.cycleThreshold = InitialThreshold gch.stat.collections = 0 gch.stat.maxThreshold = 0 gch.stat.maxStackSize = 0 - gch.stat.maxStackCells = 0 - # init the rt init(gch.tempStack) Init(gch.allocated) init(gch.marked) @@ -290,7 +278,11 @@ proc doOperation(p: pointer, op: TWalkOp) = gcAssert(c != nil, "doOperation: 1") case op of waMarkGlobal: - if isAllocatedPtr(gch.region, c): + when hasThreadSupport: + # could point to a cell which we don't own and don't want to touch/trace + if isAllocatedPtr(gch.region, c): + mark(gch, c) + else: mark(gch, c) of waMarkPrecise: add(gch.tempStack, c) @@ -298,24 +290,17 @@ proc nimGCvisit(d: pointer, op: int) {.compilerRtl.} = doOperation(d, TWalkOp(op)) proc freeCyclicCell(gch: var TGcHeap, c: PCell) = + inc gch.stat.freedObjects prepareDealloc(c) - gcTrace(c, csCycFreed) - when logGC: writeCell("cycle collector dealloc cell", c) when reallyDealloc: rawDealloc(gch.region, c) else: gcAssert(c.typ != nil, "freeCyclicCell") zeroMem(c, sizeof(TCell)) proc sweep(gch: var TGcHeap) = - when true: - for c in gch.allocated.elementsWithout(gch.marked): - gch.allocated.excl(c) - freeCyclicCell(gch, c) - else: - for c in gch.allocated.elements(): - if not gch.marked.contains(c): - gch.allocated.excl(c) - freeCyclicCell(gch, c) + for c in gch.allocated.elementsExcept(gch.marked): + gch.allocated.excl(c) + freeCyclicCell(gch, c) proc markGlobals(gch: var TGcHeap) = for i in 0 .. < globalMarkersLen: globalMarkers[i]() @@ -465,12 +450,10 @@ proc collectCTBody(gch: var TGcHeap) = markGlobals(gch) sweep(gch) - inc(gch.stat.stackScans) inc(gch.stat.collections) deinit(gch.marked) init(gch.marked) - gch.cycleThreshold = max(InitialCycleThreshold, getOccupiedMem() * - cycleIncrease) + gch.cycleThreshold = max(InitialThreshold, getOccupiedMem().mulThreshold) gch.stat.maxThreshold = max(gch.stat.maxThreshold, gch.cycleThreshold) sysAssert(allocInv(gch.region), "collectCT: end") @@ -494,7 +477,7 @@ when not defined(useNimRtl): proc GC_setStrategy(strategy: TGC_Strategy) = nil proc GC_enableMarkAndSweep() = - gch.cycleThreshold = InitialCycleThreshold + gch.cycleThreshold = InitialThreshold proc GC_disableMarkAndSweep() = gch.cycleThreshold = high(gch.cycleThreshold)-1 @@ -512,13 +495,10 @@ when not defined(useNimRtl): GC_disable() result = "[GC] total memory: " & $getTotalMem() & "\n" & "[GC] occupied memory: " & $getOccupiedMem() & "\n" & - "[GC] stack scans: " & $gch.stat.stackScans & "\n" & - "[GC] stack cells: " & $gch.stat.maxStackCells & "\n" & "[GC] collections: " & $gch.stat.collections & "\n" & "[GC] max threshold: " & $gch.stat.maxThreshold & "\n" & - "[GC] max cycle table size: " & $gch.stat.cycleTableSize & "\n" & + "[GC] freed objects: " & $gch.stat.freedObjects & "\n" & "[GC] max stack size: " & $gch.stat.maxStackSize & "\n" - when traceGC: writeLeakage() GC_enable() {.pop.} |