Hardware equipment and software environment for the z/VM large memory tests
To perform our large memory tests, we created a customer-like environment. We configured the hardware and software for both the client and the server.
Host hardware
One LPAR on a 16-way System z9™, type 2094-S18, equipped with:
| System/Guest | Storage | Dedicated CPUs | |
| Central | Expanded | ||
| z/VM LPAR | 80 GB | 4 GB | 10 |
- 1 OSA Express 2 gigabit Ethernet card (OSA code level 0805) with two ports
- Each of the five guests required 1 Ethernet card
- 8 FICON® express
cards (each card had 2 ports)
- Each storage server was connected via 8 FICON paths
Network setup
The z/VM LPAR was connected to the clients via two Fiber Gigabit Ethernet Interfaces.
Storage server setup
- IBM 3390 disk models 3 and 9
- Physical DDMS with 15,000 RPMs
- Linux® and
database disks
- Linux SLES10 GA system was installed on six 3390 mod-3s and the Linux SLES10 SP1 system was installed on three 3390 mod-9s
- The database was defined on five 3390 mod-9s. Each set of five database disks was defined on the same rank. For the ten guests, a total of ten ranks were used for the database disks.
- z/VM paging space
The second storage server was used for the disks needed for the z/VM system and paging space.
z/VM guest setup
The z/VM recommendation for the paging setup is to not use more than 50% of the DASD paging space. Following this recommendation, the setup should have a minimum of 152 GB of DASD paging space ((160 GB guests memory - 84 GB total memory) * 2).
Total pages allocated for z/VM paging space was 37,256,192 pages.
Paging space defined was 1.66 times the number of pages defined for storage and expanded storage.
Paging space was distributed across 31 3390 mod-3s and 10 3390 mod-9s as shown in Table 2. This was done to get a high I/O bandwidth for the paging I/O.
| Enterprise Storage Server® 1 (mod3s) | Enterprise Storage Server 2 (mod 9s) | ||
| Rank | Number of Disks | Rank | Number of Disks |
| 1 | 5 | 1 | 1 |
| 2 | 6 | 2 | 1 |
| 3 | 6 | 3 | 1 |
| 4 | 6 | 4 | 1 |
| 5 | 6 | 5 | 1 |
| 6 | 2 | 6 | 1 |
| 7 | 1 | ||
| 8 | 1 | ||
| 9 | 1 | ||
| 10 | 1 | ||
Table 3 shows the z/VM guest configuration we used for our tests.
| System/Guest | Memory | # of Virtual CPUs |
|---|---|---|
| Database server guest 1-10 | 16 GB | 3 |
Client hardware
One through ten x330 PCs with two Intel® 1.26 Ghz processors.
The workload driver ran on each client and only one client was attached to each guest database server.
Software setup
| Product | Version/Level |
|---|---|
| Red Hat Enterprise Linux | RHEL 4 ES (clients) |
| SUSE Linux Enterprise Server | SLES10 GA (kernel level 2.6.16.21-0.8) |
| z/VM | z/VM Version 5 Release 2.0, service level 0501 (64-bit) |
- In order to enable CMMA and VMRM-CMM the following z/VM APAR fixes are required: VM64297, VM64253, VM63968, VM64225, VM64226, VM64228. SLES10 SP1 needs the patch for bugzilla bug 38500, which is available in kernel-default-2.6.16.53-0.16.s390x.rpm from the Novell support center.
- Use of CMMA requires SLES10 SP1 or higher.
- With SLES10 SP1, we also needed to set QDIOASSIST OFF for each guest virtual machine. When a fix is available for z/VM APAR VM64287, QDIOASSIST ON should function correctly.