[Twisted-web] caching branch
Andrea Arcangeli
andrea at cpushare.com
Thu Feb 17 23:31:51 MST 2005
On Fri, Feb 18, 2005 at 06:37:35AM +0100, Andrea Arcangeli wrote:
> I'll post an updated patch suitable for merging with the
> high-performance code as soon as I finish to port it and test it.
here we go, I improved it even further, now it handles 225-230req/sec vs
180req/sec with still full html caching with the cleaner but
significantly slower ICache adapter. I found that not doing any deferred
stuff at all, even if it risks to call multiple rendering paysoff
measurably since the fast path won't have to execute a number of checks.
I doubt it can get any faster than 230req/sec without moving into
twisted space. But 230 are more than enough ;), not comparable to the
~5req/sec I get w/o caching.
This below is the diff against the caching branch (and it should really
be applied at least to the caching branch since there's no way the
ICache on top of tags.cached like in current caching branch can reach
the same performance I get with the below). Note the API is absolutely
unchanged, I had not to change a line of my app after I ported it to the
caching branch the first time. Don't get me wrong the ICache is nice,
but the only point of the cache is to go _fast_, the nicer (and slower)
stuff already happens during the real rendering. Still it's fine to use
ICache in the tags.cached since tags.cached has somewhat lower
performance priority and it remains a very significant optimization.
--- Nevow/nevow/rend.py.~1~ 2005-02-18 04:39:54.208615490 +0100
+++ Nevow/nevow/rend.py 2005-02-18 07:13:57.082073549 +0100
@@ -30,6 +30,7 @@ from nevow import tags
from nevow import flat
from nevow.util import log
from nevow import util
+from nevow import url
import formless
from formless import iformless
@@ -375,6 +376,8 @@ class ChildLookupMixin(FreeformChildMixi
self.children[name] = child
+_CACHE = {}
+
class Page(Fragment, ConfigurableFactory, ChildLookupMixin):
"""A page is the main Nevow resource and renders a document loaded
via the document factory (docFactory).
@@ -387,11 +390,38 @@ class Page(Fragment, ConfigurableFactory
beforeRender = None
afterRender = None
addSlash = None
+
cache = False
lifetime = -1
+ __lastCacheRendering = 0
flattenFactory = flat.flattenFactory
+ def hasCache(self, ctx):
+ if not self.cache:
+ return
+
+ _now = now() # run gettimeofday only once
+ timeout = _now > self.__lastCacheRendering + self.lifetime and \
+ self.lifetime >= 0
+ c = self.lookupCache(ctx)
+ if timeout or c is None:
+ # stop other renders
+ self.__lastCacheRendering = _now
+ c = None
+ return c
+ def cacheRendered(self, ctx, c):
+ if not self.cache:
+ return
+ # overwrite the deferred with the data
+ self.storeCache(ctx, c)
+ def cacheIDX(self, ctx):
+ return str(url.URL.fromContext(ctx))
+ def storeCache(self, ctx, c):
+ _CACHE[self.cacheIDX(ctx)] = c
+ def lookupCache(self, ctx):
+ return _CACHE.get(self.cacheIDX(ctx))
+
def renderHTTP(self, ctx):
## XXX request is really ctx now, change the name here
request = inevow.IRequest(ctx)
@@ -413,11 +443,18 @@ class Page(Fragment, ConfigurableFactory
if self.afterRender is not None:
self.afterRender(ctx)
- if self.buffered:
+ c = self.hasCache(ctx)
+ if c is not None:
+ finishRequest()
+ return c
+
+ if self.buffered or self.cache:
io = StringIO()
writer = io.write
- def finisher(result):
- request.write(io.getvalue())
+ def finisher(result):
+ c = io.getvalue()
+ self.cacheRendered(ctx, c)
+ request.write(c)
finishRequest()
return result
else:
@@ -427,9 +464,6 @@ class Page(Fragment, ConfigurableFactory
return result
doc = self.docFactory.load()
- if self.cache:
- name = url.URL.fromContext(ctx).path
- doc = tags.cached(name, self.lifetime)[doc]
ctx = WovenContext(ctx, tags.invisible[doc])
return self.flattenFactory(doc, ctx, writer, finisher)
@@ -504,7 +538,6 @@ class Page(Fragment, ConfigurableFactory
else:
## Use the redirectAfterPost url
ref = str(redirectAfterPost)
- from nevow import url
refpath = url.URL.fromString(ref)
magicCookie = str(now())
refpath = refpath.replace('_nevow_carryover_', magicCookie)
And this below is the patch of caching branch from dialtone + my above
incremental patch that speedup the rend.Page caching without changing
the API at all, all against trunk (i.e. the code that's going online in
a few more minutes ;).
Note that the original bugreport I sent in this thread is still
unsolved, I've no idea why the current caching branch doesn't work in
rend.Page, and I recommend dialtone to look into it, just in case the
same bug can happen even while using tags.cached normally (and I use
tags.cached normally too to cache some component).
I think the below might be good enough for merging into trunk too.
Index: Nevow/nevow/tags.py
===================================================================
--- Nevow/nevow/tags.py (revision 1228)
+++ Nevow/nevow/tags.py (working copy)
@@ -25,7 +25,7 @@
"""
-from nevow.stan import Proto, Tag, directive, raw, xml, CommentProto, invisible, slot, cdata
+from nevow.stan import Proto, Tag, directive, raw, xml, CommentProto, invisible, slot, cdata, cached
comment = CommentProto()
@@ -62,7 +62,9 @@
def inlineJS(s):
return script(type="text/javascript", language="JavaScript")[xml('\n//<![CDATA[\n%s\n//]]>\n' % s)]
-__all__ = tags + ['invisible', 'comment', '_dir', '_del', '_object', '_map', 'drange', 'Tag', 'directive', 'xml', 'raw', 'slot', 'cdata', 'inlineJS'] + ['_%s' % x for x in range(100)]
+__all__ = tags + ['invisible', 'comment', '_dir', '_del', '_object',
+ '_map', 'drange', 'Tag', 'directive', 'xml', 'raw',
+ 'slot', 'cached', 'cdata', 'inlineJS'] + ['_%s' % x for x in range(100)]
########################
Index: Nevow/nevow/__init__.py
===================================================================
--- Nevow/nevow/__init__.py (revision 1228)
+++ Nevow/nevow/__init__.py (working copy)
@@ -138,6 +138,8 @@
nevow.util.remainingSegmentsFactory nevow.context.RequestContext nevow.inevow.IRemainingSegments
nevow.util.currentSegmentsFactory nevow.context.RequestContext nevow.inevow.ICurrentSegments
+nevow.cache.SiteCache nevow.context.SiteContext nevow.inevow.ICache
+
nevow.query.QueryContext nevow.context.WovenContext nevow.inevow.IQ
nevow.query.QueryLoader nevow.inevow.IDocFactory nevow.inevow.IQ
nevow.query.QueryList __builtin__.list nevow.inevow.IQ
@@ -186,6 +188,7 @@
nevow.flat.flatstan.RendererSerializer nevow.inevow.IRenderer
nevow.flat.flatstan.DirectiveSerializer nevow.stan.directive
nevow.flat.flatstan.SlotSerializer nevow.stan.slot
+nevow.flat.flatstan.CachedSerializer nevow.stan.cached
nevow.flat.flatstan.ContextSerializer nevow.context.WovenContext
nevow.flat.flatstan.DeferredSerializer twisted.internet.defer.Deferred
nevow.flat.flatstan.DeferredSerializer twisted.internet.defer.DeferredList
Index: Nevow/nevow/flat/flatstan.py
===================================================================
--- Nevow/nevow/flat/flatstan.py (revision 1228)
+++ Nevow/nevow/flat/flatstan.py (working copy)
@@ -8,11 +8,15 @@
from nevow import util
from nevow.stan import Proto, Tag, xml, directive, Unset, invisible
-from nevow.inevow import IRenderer, IRendererFactory, IGettable, IData
-from nevow.flat import precompile, serialize
+from nevow.inevow import IRenderer, IRendererFactory, IGettable, IData, ICache
+from nevow.flat import precompile, serialize, iterflatten
from nevow.accessors import convertToData
from nevow.context import WovenContext
+from time import time as now
+from cStringIO import StringIO
+from twisted.internet import defer
+
allowSingleton = ('img', 'br', 'hr', 'base', 'meta', 'link', 'param', 'area',
'input', 'col', 'basefont', 'isindex', 'frame')
@@ -226,6 +230,43 @@
return serialize(original.default, context)
return serialize(data, context)
+def CachedSerializer(original, context):
+ cache = ICache(original.scope(context))
+ cached = cache.get(original.key, original.lifetime)
+ if cached:
+ yield cached
+ return
+ io = StringIO()
+ for child in iterflatten(original.children, context, io.write,
+ lambda item: True):
+ if isinstance(child, tuple):
+ childDeferred, childReturner = child
+
+ d = defer.Deferred() ## A new deferred for the outer loop, whose result
+ ## we don't care about, because we don't want the outer loop to write
+ ## anything when this deferred fires -- only when the entire for loop
+ ## has completed and we have all the "children" flattened
+
+ def innerDeferredResultAvailable(result):
+ childReturner(result) ## Cause the inner iterflatten to continue
+ d.callback('') ## Cause the outer iterflatten to continue
+ return ''
+
+ childDeferred.addCallback(innerDeferredResultAvailable)
+
+ ## Make the outer loop wait on our new deferred.
+ ## We call the new deferred back with ''
+ ## Which will cause the outer loop to write '' to the request,
+ ## which doesn't matter. It will then call our "returner",
+ ## which is just the noop lambda below, because we don't care
+ ## about the return result of the new deferred, which is just
+ ## ''
+
+ yield d, lambda result: ''
+ result = io.getvalue()
+ cache.set(result, original.key)
+ yield result
+
def ContextSerializer(original, context):
originalContext = original.clone(deep=False)
originalContext.precompile = context and context.precompile or False
Index: Nevow/nevow/stan.py
===================================================================
--- Nevow/nevow/stan.py (revision 1228)
+++ Nevow/nevow/stan.py (working copy)
@@ -119,8 +119,40 @@
"""
raise NotImplementedError, "Stan slot instances are not iterable."
+def passThrough(_):
+ return _
+class cached(object):
+ """Marker for cached content
+ """
+ __slots__ = ['key', 'children', 'lifetime', 'scope']
+ def __init__(self, key, scope=None, lifetime=-1):
+ self.key = key
+ self.children = []
+ self.lifetime = lifetime
+ self.scope = scope
+ if not scope:
+ self.scope = passThrough
+
+
+ def __repr__(self):
+ return "cached('%s','%s')" % self.key, self.lifetime
+
+ def __getitem__(self, children):
+ """cached content is what is being cached
+ """
+ if not isinstance(children, (list, tuple)):
+ children = [children]
+ self.children.extend(children)
+ return self
+
+ def __iter__(self):
+ """Prevent an infinite loop if someone tries to do
+ for x in cached('foo'):
+ """
+ raise NotImplementedError, "Stan slot instances are not iterable."
+
class Tag(object):
"""Tag instances represent XML tags with a tag name, attributes,
and children. Tag instances can be constructed using the Prototype
Index: Nevow/nevow/inevow.py
===================================================================
--- Nevow/nevow/inevow.py (revision 1228)
+++ Nevow/nevow/inevow.py (working copy)
@@ -98,8 +98,24 @@
ANY python object is said to implement IData.
"""
+class ICache(compy.Interface):
+ """This object represents the cache that contains all the
+ pre-flattened fragments
+ """
+ def get(self, index, lifetime):
+ """ Get an object from the cache with the given index only if
+ it is less old than lifetime, otherwise return None.
+ """
+ def set(self, toBeCached, *indexes):
+ """ Register toBeCached with each of the indexes passed """
+ def clear(self, what):
+ """ Clear what keyed element from the cache, or search for
+ what in sequences in all the keys and clear the item
+ """
+
+
class IGettable(compy.Interface):
def get(self, context):
"""Return the data
Index: Nevow/nevow/rend.py
===================================================================
--- Nevow/nevow/rend.py (revision 1228)
+++ Nevow/nevow/rend.py (working copy)
@@ -30,6 +30,7 @@
from nevow import flat
from nevow.util import log
from nevow import util
+from nevow import url
import formless
from formless import iformless
@@ -375,6 +376,8 @@
self.children[name] = child
+_CACHE = {}
+
class Page(Fragment, ConfigurableFactory, ChildLookupMixin):
"""A page is the main Nevow resource and renders a document loaded
via the document factory (docFactory).
@@ -388,8 +391,37 @@
afterRender = None
addSlash = None
+ cache = False
+ lifetime = -1
+ __lastCacheRendering = 0
+
flattenFactory = flat.flattenFactory
+ def hasCache(self, ctx):
+ if not self.cache:
+ return
+
+ _now = now() # run gettimeofday only once
+ timeout = _now > self.__lastCacheRendering + self.lifetime and \
+ self.lifetime >= 0
+ c = self.lookupCache(ctx)
+ if timeout or c is None:
+ # stop other renders
+ self.__lastCacheRendering = _now
+ c = None
+ return c
+ def cacheRendered(self, ctx, c):
+ if not self.cache:
+ return
+ # overwrite the deferred with the data
+ self.storeCache(ctx, c)
+ def cacheIDX(self, ctx):
+ return str(url.URL.fromContext(ctx))
+ def storeCache(self, ctx, c):
+ _CACHE[self.cacheIDX(ctx)] = c
+ def lookupCache(self, ctx):
+ return _CACHE.get(self.cacheIDX(ctx))
+
def renderHTTP(self, ctx):
## XXX request is really ctx now, change the name here
request = inevow.IRequest(ctx)
@@ -411,11 +443,18 @@
if self.afterRender is not None:
self.afterRender(ctx)
- if self.buffered:
+ c = self.hasCache(ctx)
+ if c is not None:
+ finishRequest()
+ return c
+
+ if self.buffered or self.cache:
io = StringIO()
writer = io.write
def finisher(result):
- request.write(io.getvalue())
+ c = io.getvalue()
+ self.cacheRendered(ctx, c)
+ request.write(c)
finishRequest()
return result
else:
@@ -499,7 +538,6 @@
else:
## Use the redirectAfterPost url
ref = str(redirectAfterPost)
- from nevow import url
refpath = url.URL.fromString(ref)
magicCookie = str(now())
refpath = refpath.replace('_nevow_carryover_', magicCookie)
Index: Nevow/nevow/guard.py
===================================================================
--- Nevow/nevow/guard.py (revision 1228)
+++ Nevow/nevow/guard.py (working copy)
@@ -24,7 +24,7 @@
from twisted.protocols import http
# Nevow imports
-from nevow import inevow, url, stan
+from nevow import inevow, url, stan, cache
def _sessionCookie():
@@ -315,6 +315,7 @@
path="/%s" % '/'.join(request.prepath),
secure=secure)
sz = self.sessions[newCookie] = self.sessionFactory(self, newCookie)
+ sz.setComponent(inevow.ICache, cache.SessionCache())
sz.args = request.args
sz.fields = getattr(request, 'fields', {})
sz.content = request.content
As usual this below nosense, no idea why it fixed things for me...
Index: Nevow/nevow/vhost.py
===================================================================
--- Nevow/nevow/vhost.py (revision 1228)
+++ Nevow/nevow/vhost.py (working copy)
@@ -19,7 +19,7 @@
"""
def getStyleSheet(self):
- return self.stylesheet
+ return VirtualHostList.stylesheet
def data_hostlist(self, context, data):
return self.nvh.hosts.keys()
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