May 2009

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This VMworld Thing is Like Watching a Train Wreck

Saturday, May 30, 2009 in Microsoft, Virtualization by slowe | 22 comments

Watching VMware destroy their public image over this VMworld exhibitor agreement is like watching a train wreck: you want to take your eyes off of it, but it’s just so awful and so terrible that you’re mesmerized.

In case you don’t have any idea what’s going on, jump over and give this post a quick read. Done? OK, let’s continue.

In the update to that post, I said that VMware had clarified their position and that competition would be allowed at VMworld. Being the person that I am—I tend to take people at their word and trust that they are as honest and straightforward as I am—I left it at that. I was a bit curious to know why the exhibitors’ agreement contained language that was specifically targeted at their competition if all they wanted was a way to prevent exhibitors from behaving in an unseemly fashion, but rather than stirring up waters that had already been muddied I would just let things settle and see what happened.

Well, what happened was that Brian Madden—whom I have no reason not to trust, but at the same time I don’t know him personally—reports here that VMware is restricting the size of the booth that both Microsoft and Citrix are allowed to use. According to Brian, only VMware TAP Partners are allowed larger booths.

Alessandro Perilli—whom I do know personally, and I whom I know wouldn’t publish anything unless he was quite certain of his sources—also refers to Brian’s post in his own post here, lending further credibility to the claims of VMware’s actions.

So, let’s sum it up:

  • VMware adds language to their exhibitors’ agreement that is specifically targeted at their competitors in an effort to prevent unseemly behavior at VMworld.
  • VMware claims that competition will be allowed and they want to encourage a rich ecosystem of partners and competitors.
  • VMware limits their two key competitors, Microsoft and Citrix, to a 10 foot-by-10 foot booth, and further states that exhibitor employees must remain in the boundaries of their booth. (To be fair, VMware is also refusing to take their money for a larger booth.)

I tell my kids all the time, “Actions speak louder than words.” What would you derive from VMware’s actions?

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VMware, This is Wrong

Thursday, May 28, 2009 in Microsoft, Virtualization by slowe | 11 comments

UPDATE: VMware has clarified their position; they will allow competitors to exhibit at VMworld. The text in the exhibitors agreement was legalese—supposedly consistent with other major vendor-sponsored conferences—meant to give them an out in the event an exhibitor behaves inappropriately.

I sincerely hope that Brian Madden is wrong about the recent change to vendor policies for VMworld.

This is exactly the wrong thing to do in this sort of competitive landscape. You know, earlier this week on the Virtual Thoughts podcast, I was defending VMworld’s move into the territory of their former ISVs with products like vCenter Data Recovery, vCenter Chargeback, and vCenter ConfigControl. After all, VMware is a publicly owned company, and they have to show value to their shareholders. But this? This doesn’t have anything to do with showing value to the shareholders. This is like a spoiled little kid saying, “This is my sandbox, and you can’t play in it.”

What are you going to do, VMware? Let’s see, you’re expanding into the territory formerly handled by many of your ISVs, and now you’re blocking access to competing products at VMworld. So who will be at VMworld? Let’s see…

  • Vizioncore can’t come, because vRanger Pro overlaps functionality VMware will provide in vCenter Data Recovery. And vFoglight overlaps with CapacityIQ.
  • VKernel can’t come; again, they overlap with CapacityIQ.
  • As Brian Madden mentioned, Quest won’t be there due to a conflict with VMware View.
  • Microsoft won’t be there, because they won’t be able to talk about Hyper-V. True, they could come and not talk about Hyper-V, but I suspect they’ll also act like a spoiled child by saying, “If we can’t play by our rules, we won’t play at all.” Hmm…considering 90-95% of all the workloads running on VMware are Microsoft Windows, that’s an interesting situation to create. Oh, and VMware: are you prepared to be excluded from Tech-Ed too?
  • Ditto for Citrix. And probably ditto for being allowed to exhibit at Synergy. So much for VMware vSphere being the best platform on which to run XenApp—you won’t get the chance to make that claim!
  • Leostream? Nope—conflicts/overlaps with VMware View.
  • What about Hyper9? Not sure, vCenter Server 4.0 does provide a Search feature now, so that could potentially preclude Hyper9 from coming, too.
  • Surely Veeam could come, but they can’t talk about Veeam Backup (conflicts with vCenter Data Recovery).
  • esXpress? Nope.
  • Hardware vendors—IBM, HP, Dell—will be there.
  • Storage vendors—EMC, NetApp, HP, Compellent, Dell—will be there.
  • Networking vendors like Cisco and HP will be there. Unless VMware thinks that HP’s networking functionality isn’t complementary enough to its own virtual networking functionality…

I’m sure that I’ve overlooked some companies, but it sounds to me like the vast majority of the third-party ISVs now find themselves precluded from exhibiting at VMworld, in addition to finding themselves competing head-to-head with VMware in their own markets. Looks like the exhibit hall is going to be a lot less crowded this year!

Is VMware the new Microsoft? I’ll let you answer that one on your own.

Disclaimer: Before anyone jumps the gun and says otherwise, note that these opinions are mine, and are not endorsed by my employer or any vendor or other organization.

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Strange Error with Firefly Media Server, iTunes, and Avahi

Saturday, May 23, 2009 in Linux, Macintosh, Networking by slowe | 1 comment

Over the 2008-2009 holiday season, I rebuilt my home network. I included the notes and information from my home network rebuild in an article that described the Mac OS X-Ubuntu integration resulting from the rebuild. Since that time, I’ve added a larger hard drive to the home server to make more room for Time Machine backups, movies, music, and other files. Things seemed to be working very well. Until the other day…

My wife made an offhand comment that she couldn’t access the shared music library from her laptop. I tested the connection and, sure enough, every time I clicked the shared library icon it simply disappeared. No error, no warning, no entries in any log files…it just disappeared. I searched the Windows event logs, and I searched the log files on the Ubuntu server downstairs. Neither computer had any entries whatsoever that provided any insight as to why this one computer would not connect to the shared music library.

Being the geeky troubleshooter that I am, I attempted to replicate the problem on some of the other computers on the network. My MacBook Pro worked fine. Three other Windows laptops on the network, running the same version of Windows (Windows XP Professional) and the same Service Pack revision, also worked fine. The problem seemed to be isolated to her computer. Perhaps it was only when she was on the wireless network…nope, the same problem regardless of the network connection.

I upgraded iTunes to the latest version. That didn’t work. I disabled the Windows Firewall on her computer. That didn’t work. I made sure that no traffic was being blocked by the firewall on the Ubuntu server; no traffic was being blocked. In other words, that didn’t work. I was about to give up and just write it off as one of those strange aberrations that couldn’t be resolved and chalk it up to Windows.

Then I stumbled onto this site. I’d already created a daapd.service file for Avahi to use previously, but this site described some additional entries in the daapd.service file that I didn’t have. I made some edits, based on the information on the site, and here’s the daapd.service file I had for Avahi:

<?xml version="1.0" standalone='no'?><!--*-nxml-*-->
<!DOCTYPE service-group SYSTEM “avahi-service.dtd”>
<service-group>
<name replace-wildcards=”yes”>Home Media Server</name>
<service>
<type>_daap._tcp</type>
<port>3689</port>
<txt-record>txtvers=1</txt-record>
<txt-record>iTSh Version=131073</txt-record>
<txt-record>Version=196610</txt-record>
</service>
</service-group>

After changing the daapd.service file to the version listed above, I restarted Avahi. Upon the shared media server re-appearing in iTunes, I clicked on it and…drum roll please…it worked! The previous version I had been using did not have the txt-record entries, and I really have no idea why adding the txt-record entries suddenly made my wife’s iTunes connect properly. I suppose it doesn’t matter why it works, it just matters that I FIXED IT! (ePlus engineers who attended our NSM this year will get this joke.)

Still, in the event you’re running into the same issue—a Windows installation of iTunes that fails to connect to a shared music library running on Firefly Media Server—then perhaps updating your Avahi configuration will correct the problem.

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VMware vSphere vDS, VMkernel Ports, and Jumbo Frames

Thursday, May 21, 2009 in Gestalt, Networking, Storage, Virtualization by slowe | 25 comments

In April 2008, I wrote an article on how to use jumbo frames with VMware ESX and IP-based storage (NFS or iSCSI). It’s been a pretty popular post, ranking right up there with the ever-popular article on VMware ESX, NIC teaming, and VLAN trunks.

Since I started working with VMware vSphere (now officially available as of 5/21/2009), I have been evaluating how to replicate the same sort of setup using ESX/ESXi 4.0. For the most part, the configuration of VMkernel ports to use jumbo frames on ESX/ESXi 4.0 is much the same as with previous versions of ESX and ESXi, with one significant exception: the vNetwork Distributed Switch (vDS, what I’ll call a dvSwitch). After a fair amount of testing, I’m pleased to present some instructions on how to configure VMkernel ports for jumbo frames on a dvSwitch.

How I Tested

The lab configuration for this testing was pretty straightforward:

  • For the physical server hardware, I used a group of HP ProLiant DL385 G2 servers with dual-core AMD Opteron processors and a quad-port PCIe Intel Gigabit Ethernet NIC.
  • All the HP ProLiant DL385 G2 servers were running the GA builds of ESX 4.0, managed by a separate physical server running the GA build of vCenter Server.
  • The ESX servers participated in a DRS/HA cluster and a single dvSwitch. The dvSwitch was configured for 4 uplinks. All other settings on the dvSwitch were left at the defaults.
  • For the physical switch infrastructure, I used a Cisco Catalyst 3560G running Cisco IOS version 12.2(25)SEB4.
  • For the storage system, I used an older NetApp FAS940. The FAS940 was running Data ONTAP 7.2.4.

Keep in mind that these procedures or commands may be different in your environment, so plan accordingly.

Physical Network Configuration

Refer back to my first article on jumbo frames to review the Cisco IOS commands for configuring the physical switch to support jumbo frames. Once the physical switch is ready to support jumbo frames, you can proceed with configuring the virtual environment.

Virtual Network Configuration

The virtual network configuration consists of several steps. First, you must configure the dvSwitch to support jumbo frames by increasing the MTU. Second, you must create a distributed virtual port group (dvPort group) on the dvSwitch. Finally, you must create the VMkernel ports with the correct MTU. Each of these steps is explained in more detail below.

Setting the MTU on the dvSwitch

Setting the MTU on the dvSwitch is pretty straightforward:

  1. In the vSphere Client, navigate to the Networking inventory view (select View > Inventory > Networking from the menu).
  2. Right-click on the dvSwitch and select Edit Settings.
  3. From the Properties tab, select Advanced.
  4. Set the MTU to 9000.
  5. Click OK.

That’s it! Now, if only the rest of the process was this easy…

By the way, this same area is also where you can enable Cisco Discovery Protocol support for the dvSwitch, as I pointed out in this recent article.

Creating the dvPort Group

Like setting the MTU on the dvSwitch, this process is pretty straightforward and easily accomplished using the vSphere Client:

  1. In the vSphere Client, navigate to the Networking inventory view (select View > Inventory > Networking from the menu).
  2. Right-click on the dvSwitch and select New Port Group.
  3. Set the name of the new dvPort group.
  5. Set the number of ports for the new dvPort group.
  6. In the vast majority of instances, you’ll want to set VLAN Type to VLAN and then set the VLAN ID accordingly. (This is the same as setting the VLAN ID for a port group on a vSwitch.)
  7. Click Next.
  8. Click Finish.

See? I told you it was pretty straightforward. Now on to the final step which, unfortunately, won’t be quite so straightforward or easy.

Creating a VMkernel Port With Jumbo Frames

Now things get a bit more interesting. As of the GA code, the vSphere Client UI still does not expose an MTU setting for VMkernel ports, so we are still relegated to using the esxcfg-vswitch command (or the vicfg-vswitch command in the vSphere Management Assistant—or vMA—if you are using ESXi). The wrinkle comes in the fact that we want to create a VMkernel port attached to a dvPort ID, which is a bit more complicated than simply creating a VMkernel port attached to a local vSwitch.

Disclaimer: There may be an easier way than the process I describe here. If there is, please feel free to post it in the comments or shoot me an e-mail.

First, you’ll need to prepare yourself. Open the vSphere Client and navigate to the Hosts and Clusters inventory view. At the same time, open an SSH session to one of the hosts you’ll be configuring, and use “su -” to assume root privileges. (You’re not logging in remotely as root, are you?) If you are using ESXi, then obviously you’d want to open a session to your vMA and be prepared to run the commands there. I’ll assume you’re working with ESX.

This is a two-step process. You’ll need to repeat this process for each VMkernel port that you want to create with jumbo frame support.

Here are the steps to create a jumbo frames-enabled VMkernel port:

  1. Select the host and and go the Configuration tab.
  2. Select Networking and change the view to Distributed Virtual Switch.
  3. Click the Manage Virtual Adapters link.
  4. In the Manage Virtual Adapters dialog box, click the Add link.
  5. Select New Virtual Adapter, then click Next.
  6. Select VMkernel, then click Next.
  7. Select the appropriate port group, then click Next.
  8. Provide the appropriate IP addressing information and click Next when you are finished.
  9. Click Finish. This returns you to the Manage Virtual Adapters dialog box.

From this point on you’ll go the rest of the way from the command line. However, leave the Manage Virtual Adapters dialog box open and the vSphere Client running.

To finish the process from the command line:

  1. Type the following command (that’s a lowercase L) to show the current virtual switching configuration:
    esxcfg-vswitch -l
    At the bottom of the listing you will see the dvPort IDs listed. Make a note of the dvPort ID for the VMkernel port you just created using the vSphere Client. It will be a larger number, like 266 or 139.
  2. Delete the VMkernel port you just created:
    esxcfg-vmknic -d <dvPort ID>
  3. Recreate the VMkernel port and attach it to the very same dvPort ID:
    esxcfg-vmknic -a -i <IP addr> -n <Mask> -m 9000 <dvPort ID>
  4. Use the esxcfg-vswitch command again to verify that a new VMkernel port has been created and attached to the same dvPort ID as the original VMkernel port.

At this point, you can go back into the vSphere Client and enable the VMkernel port for VMotion or FT logging. I’ve tested jumbo frames using VMotion and everything is fine; I haven’t tested FT logging with jumbo frames as I don’t have FT-compatible CPUs. (Anyone care to donate some?)

As I mentioned in yesterday’s Twitter post, I haven’t conducted any objective performance tests yet, so don’t ask. I can say that NFS feels faster with jumbo frames than without, but that’s purely subjective.

Let me know if you have any questions or if anyone finds a faster or easier way to accomplish this task.

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vSphere 4 Available for Download

Thursday, May 21, 2009 in Virtualization by slowe | 3 comments

As of today, May 21, 2009, the final GA builds of VMware vSphere 4—including VMware ESX 4 (build 164009), VMware ESXi 4 (build 164009), vCenter Server 4 (build 162902), VMware Consolidated Backup, VMware vCenter Data Recovery, and VMware vShield Zones are available for download from VMware’s web site.

This is an event that the VMware community has been waiting to occur for quite some time now, and it’s exciting to have the day finally here and the final code available to the general public.

Of course, I’m covering all these technologies in my upcoming Mastering VMware vSphere 4 book, available for pre-order now on Amazon and shipping in September. (By the way, I’m hearing rumors from my publisher that copies of the book may be available at VMworld 2009, but I’m not 100% sure yet. Stay tuned.)

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VMware vSphere Generates Insane Amounts of I/O

Monday, May 18, 2009 in Storage, Virtualization by slowe | 8 comments

The news has hit the Internet in various places, but I wanted to point it out here because it does help to debunk the myth that virtualization can’t handle all workload. What’s the news? EMC and VMware have jointly demonstrated that a single VMware vSphere host running just three virtual machines can drive just above 350,000 I/O operations per second (IOPS).

I’ll let that sink in for just a moment. In case you don’t understand just how significant that number is, consider that a typical Fibre Channel drive can sustain somewhere just below 200 IOPS (and that’s being a bit generous). At 200 IOPS per drive, driving 350,000 IOPS would require 1,750 drives. (Fortunately, EMC used Enterprise Flash Drives (EFDs), so far fewer drives were required.) I would wonder how many of us have actually seen a storage array with that many drives.

Chad Sakac of EMC covered the tests on his blog here; the VMware Performance blog also discussed the results in detail as well.

So, next time you are thinking that VMware vSphere can’t handle your database workloads, keep these figures in mind. Or, if you’re a consultant like me, use these figures next time your customer says that virtualization can’t handle I/O-intensive workloads. This looks like pretty definitive results to me.

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Summary of CDP Articles

Monday, May 18, 2009 in Virtualization by slowe | 3 comments

For all you data storage guys and gals out there, CDP here means “Cisco Discovery Protocol”, not “Continuous Data Protection.” Sorry.

It seems that interest in VMware ESX’s support for CDP is gaining interest and attention; fellow blogger Rich Brambley of VM /ETC recently covered the topic as well.

To help summarize some of the content that I’ve generated around VMware ESX and CDP, here is a list of the articles available on this site:

  • Identifying ESX Server NICs in Blades - Although written for the blade server environment, the information presented in this article on how to use CDP to identify NICs works just as well for rack mount servers.
  • Next-Gen Stuff: Enabling CDP in ESX/ESXi - This article describes how to enable CDP on a standard vSwitch (on both VMware ESX and VMware ESXi) as well as on a vNetwork Distributed Switch (officially abbreviated as vDS but I like to call them a dvSwitch).
  • Viewing CDP Data on VMware ESX - Using the esxcfg-info command will actually show you the CDP data that’s been collected by VMware ESX. This command is different from the command that Rich showed; I think I like Rich’s command (also shared by wharlie in the comments to my article) better.

Enjoy!

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Hyper9 Virtualization Mobile Manager Beta Invitations

Thursday, May 14, 2009 in Virtualization by slowe | 14 comments

The fine folks over at Hyper9 recently offered me a very limited number of special beta invitations for Hyper9’s new Virtualization Mobile Manager (VMM) product. As you may already know, VMM is the brainchild of Andrew Kutz, who recently joined Hyper9 and has already released a few snippets of code via H9Labs.

Here are some highlights of VMM:

  • Supports all major hypervisors: VMware Server 2, VMware Infrastructure 3 (VMware ESX and VMware ESXi 3.5, VirtualCenter 2.5), Microsoft Hyper-V, and Citrix XenServer 5
  • Runs as an Apache Tomcat web application, supported on Windows, Linux, and Mac OS X
  • Accessible from just about any mobile device: Apple iPhone, Blackberry, Google Android-based phones, and Windows Mobile devices
  • “Gracefully degrades” into Lite Mode if the mobile device doesn’t support all the web UI features

While the VMM beta is open to the general public, I have 15 special invitations that will grant additional benefits (extra perks, if you will). Specifically, these beta invitations will come with:

  • A 50% discount on the already low pricing for VMM once it is released
  • Automatic entry into a contest, starting in June, to win a mobile device
  • A limited edition Hyper9 T-shirt (assuming you provide a little feedback to the team at Hyper9)

Interested in one of these special invitations? Well, you’re going to have to work for it. Post a comment to this article telling me why you should be one of the lucky 15 readers who gets a special invitation. Telling me you’ll help promote my upcoming vSphere book might improve your chances…or it might not! I’ll leave comments open until Friday, May 22, or until I get 30 comments on the article, whichever comes first. From the comments on the article I’ll select the top 15 to receive the special invitation to the VMM beta.

In the event you aren’t interested in one of the special invitations, or if you read this article after the invitations have already been given out, you can also register for the beta from the Hyper9 community site.

So post your comment now!

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Introduction to Nehalem Memory

Monday, May 11, 2009 in General by adelp | 16 comments

By Aaron Delp
Twitter: aarondelp
FriendFeed (Delicious, Twitter, & all my blogs in one spot): aarondelp

I wanted to relay some information regarding choosing memory speeds and types for the new Intel Xeon 5500 (Nehalem family) processors. As stated in my previous article on the Nehalem CPUs, there are some decisions that need to be made when choosing the memory and processor combinations. Let’s start off with what the memory architecture looks like.

  • The current Xeon 5500 family is a two-socket configuration.
  • Memory will run at 1333 MHz, 1066 MHz, and 800 MHz.
  • Memory is currently produced in single, dual, and quad rank configurations. Dual rank is faster than single rank, quad rank is currently limited to 1066 MHz speed.
  • Each CPU socket has 3 memory channels for a total of 6 channels per server.
  • Each channel can accept up to 3 DIMMS. This is why the servers currently are made with either 12 sockets (2 DIMMS per channel x 3 channels per processor x 2 processor sockets) or 18 sockets (3 DIMMS per channel x 3 Channels per processor x 2 processor sockets).
  • Some servers come in a 16 DIMM arrangement. Please see this IBM Paper for more information.
  • The maximum memory speed is limited by processor. For example, the X5570 has a max memory speed of 1333 MHz, the E5540 has a max memory speed of 1066 MHz, etc.
  • As more memory is added to a channel, the memory will slow down.
  • Better performance is achieved when the memory is “balanced” (the total amount of memory across channels is the same).

Take a look at the Hp Quick Specs for the BL460 G6 server in the Memory section. I found this to be a great source.

So, what does all of that mean? It means that for best performance you should install the memory using the following guidelines:

  • Ideally, install DIMMs in sets of 6, 1 per channel (populate both sockets with CPUs!). Use DIMMs that are dual rank and have the fastest speed you can purchase that the processor supports.
  • Populate the first slot in all channels first, then populate the 2nd slots in all channels, etc. Don’t put all three DIMMs in one channel and leave other channels empty.
  • Balance the amount of memory in each channel whenever possible (3 x 4GB on two channels and 1 x 4GB 1 X 8GB on the last channel).
  • If at all possible, try to keep the system away from the 800MHz memory speed.

Here is link to an awesome IBM white paper explaining everything.

Here’s an example 12 DIMM slot Nehalem configuration:

Speed

Max Mem Speed

Bank 1 in Channel Populated

Bank 2 in Channel Populated

X5570 (2.93 GHZ)

1333 MHz

1333 MHz

1066 MHz *

X5560 (2.80 GHZ)

1333 MHz

1333 MHz

1066 MHz *

X5550 (2.66 GHZ)

1333 MHz

1333 MHz

1066 MHz *

E5540 (2.53 GHZ)

1066 MHz

1066 MHz

1066 MHz

E5530 (2.40 GHZ)

1066 MHz

1066 MHz

1066 MHz

E5520 (2.26 GHZ)

1066 MHz

1066 MHz

1066 MHz

E5506 (2.13 GHZ)

800 MHz

800 MHz

800 MHz

E5504 (2.00 GHZ)

800 MHz

800 MHz

800 MHz

E5502 (1.66 GHZ)

800 MHz

800 MHz

800 MHz

 

Here’s an example 18 DIMM slot Nehalem configuration:

Speed

Max Mem Speed

Bank 1 in Channel Populated

Bank 2 in Channel Populated

Bank 3 in Channel Populated

X5570 (2.93 GHZ)

1333 MHz

1333 MHz

1066 MHz *

800 MHz

X5560 (2.80 GHZ)

1333 MHz

1333 MHz

1066 MHz *

800 MHz

X5550 (2.66 GHZ)

1333 MHz

1333 MHz

1066 MHz *

800 MHz

E5540 (2.53 GHZ)

1066 MHz

1066 MHz

1066 MHz

800 MHz

E5530 (2.40 GHZ)

1066 MHz

1066 MHz

1066 MHz

800 MHz

E5520 (2.26 GHZ)

1066 MHz

1066 MHz

1066 MHz

800 MHz

E5506 (2.13 GHZ)

800 MHz

800 MHz

800 MHz

800 MHz

E5504 (2.00 GHZ)

800 MHz

800 MHz

800 MHz

800 MHz

E5502 (1.66 GHZ)

800 MHz

800 MHz

800 MHz

800 MHz

* According to the HP Quick Spec for the BL460 G6, they are able to keep the speed at 1333 MHz with 2 DIMMS. A BIOS update is required to achieve this. This is HP specific.

Common Questions:

Q: What kind of performance decrease will I see by lowering the clock speed of my memory? For example using 6×2GB DIMMs (running at 1333 MHz) vs 12 x 1 GB DIMMs (running at 1066 MHz) to save a little money.

A: According to the IBM white paper listed above, we have two main areas of performance to worry about, latency and throughput. The latency difference between 1333 MHz and 800 MHz is about 10%. Memory throughput is another story though. The different between 1333 MHz and 1066 MHz is about 9%. The difference from 1066 MHz to 800 MHz is 28%!

Q: What kind of performance increase will I see in a “balanced” (same amount of memory per channel) system?

A: Again, according to the IBM paper, you will see a performance increase if the system is balanced. An exact number isn’t given.

Q: Which is fastest? Single, dual, or quad rank DIMMS?

A: According to the IBM White Paper, dual rank outperforms single rank by 7% in Specjbb2005. Quad rank DIMMs decrease the clock speed to 1066 MHz so they are not faster at this time.

Q: What if I only populate one processor?

A: You want to populate both sockets if performance is a concern. Adding the second processor not only makes the second set of DIMM sockets available, it also doubles the memory bandwidth.

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Pre-Order Mastering VMware vSphere 4

Monday, May 11, 2009 in Virtualization by slowe | 8 comments

My forthcoming book, Mastering VMware vSphere 4, is now available for pre-order via Amazon! Click here to see all the details. The book is available with a fairly significant discount (37%), but I don’t know how long that price will last. Get it now!

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