[Zodb-checkins] CVS: ZODB3/ZEO - ClientCache.py:1.31
Guido van Rossum
guido@python.org
Fri, 30 Aug 2002 14:13:43 -0400
Update of /cvs-repository/ZODB3/ZEO
In directory cvs.zope.org:/tmp/cvs-serv25491
Modified Files:
ClientCache.py
Log Message:
Merged the cache trace code from the branch. I'm not afraid of it any
more. (ZEO1 will follow after lunch.)
=== ZODB3/ZEO/ClientCache.py 1.30 => 1.31 ===
--- ZODB3/ZEO/ClientCache.py:1.30 Wed Aug 28 14:58:35 2002
+++ ZODB3/ZEO/ClientCache.py Fri Aug 30 14:13:43 2002
@@ -101,6 +101,7 @@
"""
import os
+import time
import tempfile
from struct import pack, unpack
from thread import allocate_lock
@@ -185,6 +186,7 @@
self._limit = size / 2
self._current = current
+ self._setup_trace()
def open(self):
# Two tasks:
@@ -230,18 +232,31 @@
try:
p = self._get(oid, None)
if p is None:
+ self._trace(0x10, oid, version)
return None
f = self._f[p < 0]
ap = abs(p)
f.seek(ap)
h = f.read(27)
+ if len(h) != 27:
+ log("invalidate: short record for oid %16x "
+ "at position %d in cache file %d"
+ % (U64(oid), ap, p < 0))
+ del self._index[oid]
+ return None
if h[:8] != oid:
- return
+ log("invalidate: oid mismatch: expected %16x read %16x "
+ "at position %d in cache file %d"
+ % (U64(oid), U64(h[:8]), ap, p < 0))
+ del self._index[oid]
+ return None
f.seek(p+8) # Switch from reading to writing
if version and h[15:19] != '\0\0\0\0':
+ self._trace(0x1A, oid, version)
# There's still relevant non-version data in the cache record
f.write('n')
else:
+ self._trace(0x1C, oid, version)
del self._index[oid]
f.write('i')
finally:
@@ -252,6 +267,7 @@
try:
p = self._get(oid, None)
if p is None:
+ self._trace(0x20, oid, version)
return None
f = self._f[p < 0]
ap = abs(p)
@@ -272,15 +288,21 @@
if h[8]=='n':
if version:
+ self._trace(0x22, oid, version)
return None
if not dlen:
+ # XXX This shouldn't actually happen
+ self._trace(0x24, oid, version)
del self._index[oid]
return None
if not vlen or not version:
if dlen:
- return read(dlen), h[19:]
+ data = read(dlen)
+ self._trace(0x2A, oid, version, h[19:], dlen)
+ return data, h[19:]
else:
+ self._trace(0x26, oid, version)
return None
if dlen:
@@ -290,13 +312,17 @@
if version != v:
if dlen:
seek(p+27)
- return read(dlen), h[19:]
+ data = read(dlen)
+ self._trace(0x2C, oid, version, h[19:], dlen)
+ return data, h[19:]
else:
+ self._trace(0x28, oid, version)
return None
vdlen = unpack(">i", vheader[-4:])[0]
vdata = read(vdlen)
vserial = read(8)
+ self._trace(0x2E, oid, version, vserial, vdlen)
return vdata, vserial
finally:
self._release()
@@ -304,6 +330,7 @@
def update(self, oid, serial, version, data):
self._acquire()
try:
+ self._trace(0x3A, oid, version, serial, len(data))
if version:
# We need to find and include non-version data
p = self._get(oid, None)
@@ -345,6 +372,7 @@
try:
p = self._get(oid, None)
if p is None:
+ self._trace(0x40, oid)
return None
f = self._f[p < 0]
ap = abs(p)
@@ -364,12 +392,16 @@
return None
if h[8] == 'n':
+ self._trace(0x4A, oid)
return None
if not vlen:
+ self._trace(0x4C, oid)
return ''
seek(dlen, 1)
- return read(vlen)
+ version = read(vlen)
+ self._trace(0x4E, oid, version)
+ return version
finally:
self._release()
@@ -381,6 +413,7 @@
if self._pos + size > self._limit:
current = not self._current
self._current = current
+ self._trace(0x70)
log("flipping cache files. new current = %d" % current)
# Delete the half of the index that's no longer valid
index = self._index
@@ -406,9 +439,12 @@
finally:
self._release()
-
def store(self, oid, p, s, version, pv, sv):
self._acquire()
+ if s:
+ self._trace(0x5A, oid, version, s, len(p))
+ else:
+ self._trace(0x5C, oid, version, sv, len(pv))
try:
self._store(oid, p, s, version, pv, sv)
finally:
@@ -445,6 +481,41 @@
self._index[oid] = self._pos
self._pos += tlen
+
+ def _setup_trace(self):
+ # See if cache tracing is requested through $ZEO_CACHE_TRACE.
+ # If not, or if we can't write to the trace file,
+ # disable tracing by setting self._trace to a dummy function.
+ self._tracefile = None
+ tfn = os.environ.get("ZEO_CACHE_TRACE")
+ if tfn:
+ try:
+ self._tracefile = open(tfn, "ab")
+ self._trace(0x00)
+ except IOError:
+ self._tracefile = None
+ if self._tracefile is None:
+ def notrace(*args):
+ pass
+ self._trace = notrace
+
+ def _trace(self, code, oid='', version='', serial='', dlen=0,
+ # Remaining arguments are speed hacks
+ time_time=time.time, struct_pack=pack):
+ # The code argument is two hex digits; bits 0 and 7 must be zero.
+ # The first hex digit shows the operation, the second the outcome.
+ # If the second digit is in "02468" then it is a 'miss'.
+ # If it is in "ACE" then it is a 'hit'.
+ # This method has been carefully tuned to be as fast as possible.
+ # Note: when tracing is disabled, this method is hidden by a dummy.
+ if version:
+ code |= 0x80
+ self._tracefile.write(
+ struct_pack(">ii8s8s",
+ time_time(),
+ (dlen+255) & 0x7fffff00 | code | self._current,
+ oid,
+ serial))
def read_index(index, serial, f, fileindex):
seek = f.seek