[Zope] Re: threading in zope (ignore previous post)

Mon, 8 Jul 2002 03:19:52 -0500

I found that the 'sequential' behaviour I was
seeing from my product is an artifact of my browser.

Daniel

Daniel Mahler writes:
 > 
 > 
 > I am trying to figure out how Zope processes concurrent requests.
 > I am running Zope using ZServer
 > (without a webserver in front)
 > 
 > My initial investigations suggest contradictory answers:
 > 
 > * ZServer uses medusa,
 >   which uses asyncore which works by single threaded select multiplexing
 > 
 > * z2.py has::
 >  
 >      # The size of the thread pool, if ZODB3 is used.
 >      NUMBER_OF_THREADS=4
 > 
 >   sugesting we are running multi threaded.
 > 
 > 
 > * the following modification of the Minimal Product How-To,
 >   suggests that requests are being processed single threaded::
 > 
 >     from time import sleep, clock, time
 >     
 >     from OFS import SimpleItem
 >         
 >     class minimal(SimpleItem.SimpleItem, Thread):
 >     
 >     	"minimal object"
 >     
 >     	meta_type = 'minimal'
 >     
 >     	manage_options = (
 >     	    {'label': 'View', 'action': 'index_html'},
 >     	)
 >     
 >     	
 >     	def __init__(self, id):
 >     	    "initialise a new instance of Minimal"
 >     	    self.id = id
 >     
 >     	def index_html(self):
 >     	    "used to view content of the object"
 >     	    time1 = time()
 >     	    sleep(10)
 >     	    time2 = time()
 >     	    return '<html><body>Hello World<br>%s<br>%s<br></body></html>'%(time1,time2)
 >     	    
 >     	
 >     	def manage_addMinimal(self, id, RESPONSE=None):
 >     	    "Add a Minimal to a folder."
 >     	    self._setObject(id, minimal(id))
 >     	    RESPONSE.redirect('index_html')
 >     		
 >     	def manage_addMinimalForm(self):
 >     	    "The form used to get the instance' id from the user."
 >     	    return """<html>
 >     <body>
 >     Please type the id of the minimal instance:<br>
 >     <form name="form" action="manage_addMinimal"><br>
 >     <input type="text" name="id"><br>
 >     <input type="submit" value="add">
 >     </form>
 >     </body>
 >     </html>"""
 > 
 >   If I fire several requests to an instance of this class in rapid
 >   succession, Zope serializes them time1 of the second is after time2
 >   of the first, time1 of the third is after time2 of the second  and
 >   so on, suggesting that Zope is processing the requests purely
 >   sequentially.
 > 
 > thanks
 > Daniel