Microsoft has made a rather brave announcement that the next version of Exchange Server – version 12, due late next year – will be available only as a 64-bit product. That’s right, there will be no 32-bit version at all. The importance of this statement is hard to over-emphasise. First, it means that with the next release of server software, in the Longhorn Server timeframe, the emphasis will be entirely on 64-bit computing. No announcement has yet been made – at least that I can discover – as to whether Longhorn Server itself will be available in a 32-bit version as well as 64-bit, but I sincerely hope it won’t. You see, the time has come to move up to 64-bit and we need a bit of a poke to make us go there.
I’m sure there are people running Exchange Server 2000 or 2003 today who were hoping to get another crank of the handle out of their existing server infrastructure. I can think of one local client of mine – a well-established and successful firm of solicitors – which invested heavily some five years ago in Exchange 2000 Server (ES 2000) on Windows 2000, and made a clean sweep through its desktops too. At that time, I told the company that ES 2000 would see it through about six years, and that there would be a significant benefit in waiting for the next-but-one version before considering an upgrade. In addition, I pointed out that its servers – twin 1GHz Pentium 4s with 1GB of RAM – would by then be well past their sell-by dates and fully amortised by the business, hence ready to be demoted to a secondary role within the firm.
Due to this advice, the company decided not to buy into the rolling subscriptions from Microsoft, choosing instead to buy new again when the time was ripe. Well, it’s all now coming to fruition and no doubt I’ll be taking some hardware round to its offices next spring to demonstrate the benefits of SharePoint 12, Exchange 12 and Office 12, all running on a 64-bit server. For this client, it will represent a massive, but carefully considered, step forward beyond that first implementation of email, Web, file and print that was installed back in 2000.
Why is Exchange Server so greedy of memory and so computationally demanding that it needs a 64-bit version? Well, there are many gigabytes of data held in Exchange Servers. Even the standard version today can store up to 75GB of data, and that’s a purely artificial limit, which used to be much lower. Microsoft’s view is that venturing into the realm of hundreds of gigs of storage puts such a strain on your backup, recovery and DR (disaster recovery) infrastructure that you really ought to think about clustering at this point – which is a feature of the Enterprise version and costs a lot more money. I agree with the company, but only up to a point. It’s up to me to decide how my DR, planning and so forth will work, and the Enterprise version has enough other worthwhile features not to need any help from arbitrary storage limits in its humbler sibling.
But it isn’t only the absolute amount of data that’s being held nowadays – after all, databases have held on to vast quantities of data for many years. More important is that each Exchange Server user has his or her own inbox, and 100 mailboxes will result in 100 ‘hotspots’ in the database where emails are constantly being added, read and deleted almost in real-time. Compare this with, say, an invoicing system where the only hotspot is the current day’s trading, and where the historical data rarely gets touched at all. Worse still, Exchange Server users love to scan through their email looking for old documents, phrases or other key words, so much more of an Exchange Server database is ‘live’ compared to traditional SQL-based RDBMS implementations. That’s why Exchange Server is such a rampant consumer of memory, and 32-bit Windows Server dishes out only 2GB of application memory, on a per-application basis (this can be fiddled to 3GB by using the /3GB switch in the boot.ini file, but it’s a truly horrible kludge).