With the right design and the right know-how, anything is possible. Here's the biggest problem with this question: technologies (i.e. app servers) don't scale when you are talking at this threshold - solutions do. Zope will scale quite well, likely on par with Java app servers, but likely will do so in different ways. You don't say what kind of site this is. Much of the answer depends on how cacheable your content/pages are, how many users are required to login, etc. It also depends on how you scale (up vs. out). Zope has relatively good scalability for some types of applications, and solutions are available for clustering (ZEO), and replication (ZRS or DirectoryStorage). With some of the cutting edge stuff out there like ESI support in combination with Squid 3 (development branch of Squid), you could likely build quite large clusters of Zope servers with much of the CPU intensive work out to proxy server farms. I know the folks at Zope Corp. are doing some really heavy-duty stuff with ESI and cutting-edge versions of Squid to extend the reach of the application beyond simply the app server: anything that intends to scale to this many users would likely take this kind of approach. One note on Zope and scalability: Zope generally scales out better than it scales up, though with blade servers using fast interconnects, this distinction will largely be blurred within the next few years. Zope/Python like single-CPU affinity for groups of threads under the same process, so when you do choose to scale Zope heavily, using an OS capable of processor-binding would be a requirement (newest Linux 2.4, Solaris, etc). Low-latency for communication media between ZEO clients and the ZEO storage server are also a good idea. Sean -----Original Message----- From: GIROTTO Diego (ESPIN) [mailto:diego.girotto@espin.it] Sent: Thursday, June 26, 2003 1:33 AM To: 'zope@zope.org' Subject: [Zope] Zope - enterprise Hy, is there anyone than can tell me any link or documentation about a generic Zope site (with or without CMF) performance with 1 milion of concurrenty users? In other ways, are Zope perfomance comparable with any other application server for enterprise portals solutions? tnx at all P.S excuse me for my english --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.493 / Virus Database: 292 - Release Date: 6/25/2003