Compaq 108164-003 - ProLiant - 800 Guide de démarrage rapide

Technical Guide

Help us improve our technical communication. Let us know what you think

about the technical information in this document. Your feedback is valuable

and will help us structure future communications. Please send your

comments to: [email protected]

March 1999

ECG044.0399

Prepared by OS Integration

Engineering

Compaq Computer Corporation

Contents

Executive Summary ...................3

Introduction................................4

I/O Performance and

Recommendations .....................4

Network Interface......................5

Peripheral Component

Interconnect (PCI) Bus..............6

SCSI Bus..................................9

Fibre Channel.........................12

Drive Technology....................14

System Memory......................18

OS Performance Monitoring

Tools.........................................19

Microsoft Windows NT............20

Novell NetWare.......................21

SCO UnixWare and

OpenServer............................21

Conclusion..............................22

Appendix - Performance

Tuning Data..............................23

Fibre Channel Bus..................23

Drive Technology....................28

RAID Level Performance.........35

Hardware RAID vs. Software

RAID......................................36

I/O Performance Tuning of

Compaq Servers

Abstract: Tuning the disk system and I/O paths can be key to

achieving maximum performance from your server. This paper

begins with definitions, guidelines, and recommendations for I/O

performance tuning. The last section of this paper provides actual

performance data to reinforce recommendations. In general, this

paper deals with universal I/O concerns and applies to a wide range

of server applications. The major areas examined in this paper are

•disk systems

•NICs

•memory

•system configuration

•performance monitoring tools.

I/O Performance Tuning of Compaq Servers 2

ECG044.0399

Notice

The information in this publication is subject to change without notice and is provided “AS IS” WITHOUT

WARRANTY OF ANY KIND. THE ENTIRE RISK ARISING OUT OF THE USE OF THIS

INFORMATION REMAINS WITH RECIPIENT. IN NO EVENT SHALL COMPAQ BE LIABLE FOR

ANY DIRECT, CONSEQUENTIAL, INCIDENTAL, SPECIAL, PUNITIVE OR OTHER DAMAGES

WHATSOEVER (INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS

PROFITS, BUSINESS INTERRUPTION OR LOSS OF BUSINESS INFORMATION), EVEN IF

COMPAQ HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

The limited warranties for Compaq products are exclusively set forth in the documentation accompanying

such products. Nothing herein should be construed as constituting a further or additional warranty.

This publication does not constitute an endorsement of the product or products that were tested. The

configuration or configurations tested or described may or may not be the only available solution. This test

is not a determination or product quality or correctness, nor does it ensure compliance with any federal

state or local requirements.

Product names mentioned herein may be trademarks and/or registered trademarks of their respective

companies.

Compaq, Contura, Deskpro, Fastart, Compaq Insight Manager, LTE, PageMarq, Systempro, Systempro/LT,

ProLiant, TwinTray, ROMPaq, LicensePaq, QVision, SLT, ProLinea, SmartStart, NetFlex, DirectPlus,

QuickFind, RemotePaq, BackPaq, TechPaq, SpeedPaq, QuickBack, PaqFax, Presario, SilentCool,

CompaqCare (design), Aero, SmartStation, MiniStation, and PaqRap, registered United States Patent and

Trademark Office.

Netelligent, Armada, Cruiser, Concerto, QuickChoice, ProSignia, Systempro/XL, Net1, LTE Elite,

Vocalyst, PageMate, SoftPaq, FirstPaq, SolutionPaq, EasyPoint, EZ Help, MaxLight, MultiLock,

QuickBlank, QuickLock, UltraView, Innovate logo, Wonder Tools logo in black/white and color, and

Compaq PC Card Solution logo are trademarks and/or service marks of Compaq Computer Corporation.

Microsoft, Windows, Windows NT, Windows NT Server and Workstation, Microsoft SQL Server for

Windows NT are trademarks and/or registered trademarks of Microsoft Corporation.

NetWare and Novell are registered trademarks and intraNetWare, NDS, and Novell Directory Services are

trademarks of Novell, Inc.

NetBench and ServerBench are registered trademarks of ZDInc.

Pentium is a registered trademark of Intel Corporation.

I/O Performance Tuning of Compaq Servers

Technical Guide prepared by OS Integration Engineering

First Edition (March 1999)

Document Number ECG044.0399

I/O Performance Tuning of Compaq Servers 3

ECG044.0399

Executive Summary

In order to maximize your investment, it is crucial that you get the highest consistent performance

from your server. As the demands placed on your server grow, the hardware performance and

configuration efficiency must keep pace. However, poorly implemented expansion and upgrades,

such as, unbalanced busses and memory bottlenecks, can seriously degrade performance. For

example, simply adding or rearranging drives or adapters can, in some cases, increase the

throughput of your entire disk system by as much as 96%. While not all servers will realize gains

of this magnitude so easily, every server can be optimized to increase its functionality and

longevity.

Performance tuning may not only save money now, but may also prevent premature replacement

of viable equipment. Since technology budgets are limited, it is important to get the most out of

every investment, in terms of both performance and, especially, longevity. Less than optimal

server configuration can shorten server life cycles as network demands outpaces server

performance. In the meantime, your network clients will work less efficiently and become

frustrated as they deal with a slower network.

You can prevent the adverse effects of a slow network by making sure that your server is

delivering maximum performance. Compaq performs extensive tests to determine the optimal

configuration for different environments. The results of these tests can be invaluable tools in

configuring and tuning your server. Many of the recommendations can be implemented

immediately, some without any cost. All of these guidelines, however, prevent the maintenance

and frustrations caused by poor server performance.

By implementing the recommendations found in this paper, your server can immediately become

more responsive. The amount of maintenance and total cost of ownership required by your server

can also drop dramatically. In the long run, you will have earned a greater return on your

investment from both your server and clients.

I/O Performance Tuning of Compaq Servers 4

ECG044.0399

Introduction

Perhaps the most common term when maximizing server performance is bottleneck. Invariably,

one component in a system will be stressed more than others and, as a result, the performance of

the entire system will be limited when the limits of that device have been reached. A bottleneck is

not always a single device, and in some cases, it’s not a device at all. Often, an entire subsystem

or simply a less than optimal configuration limits performance. Given any configuration, there are

bottlenecks and, usually, the limiting factor can not be eliminated completely. Maximizing

performance for a server involves careful analysis and reconfiguration to reduce the effect of the

bottlenecks.

In order to identify and reduce the impact of the most stressed component, you must know the

hardware present and normal operating conditions for your server. As you will see, an important

factor in tuning a server is the server mix. The server mix is the ratio that expresses the amount of

server requests that are:

•random vs. sequential

•small vs. large block transfers

•reads vs. writes

By understanding what data is requested,and how often, you can decide which components are

most likely to become a bottleneck in your environment. For instance, a lightly-loaded server that

performs all random, small file transfers will most likely incur a delay as the drives seek to find

the requested data; the bus on this server remains relatively idle. On the other hand, large,

contiguous file transfers need only position the drive heads initially to begin streaming data to the

client; these requests are more likely to run into a bus saturation limitation.

Perhaps a more obvious factor in server performance is the server itself. In every server

environment, there are variables that must be considered regardless of configuration and

operation. For instance, physical drive delays as the heads are positioned over the data are present

in every computer. Performance tuning seeks to reduce the effect of individual delays on overall

system performance. This document will give general recommendations for reducing the effect of

any given delay and the role that some of the new technology can play.

I/O Performance and Recommendations

Dynamic systems, such as a network, operate within a set of boundary conditions. These

boundary conditions describe the limitations imposed by the individual components of the

system. Optimization of your system for maximum performance involves

•Knowledge of the components and their relationships

•Discovery of current performance through measurements and analysis

•Adaptation to increase performance.

The operating realm is a solution of the boundary conditions. In a graphical form, as in Figure 1,

the solution for each operating parameter is a polygon. While the system can operate anywhere

within the polygon, the boundaries of the polygon are where the system usually operates. In

particular the modes of a solution are usually at an apex of the polygon.

I/O Performance Tuning of Compaq Servers 5

ECG044.0399

Figure 1.Boundary Value Conditions Graphical Solution

In Figure 1, the Parameter axis could represent a complex, composite variable such as disk

systems or a simpler variable such as the type of disks used in a system. The performance axis is

usually the axis being optimized. The optimal solution in this example is apex 1, but operating at

2 is not to be ignored. The differences between these points could represent a 5% performance

and a 40% price difference.

In general, simply adding redundant instances of a system allows parallel

execution of that system’s task and can increase the effective performance of

that system. For instance, striping the data from a single drive onto two

physical devices can nearly double drive throughput in some cases.

Unfortunately, this is a situation of diminishing returns. In fact, adding more

than the optimal number of redundant devices can actually degrade

performance. For example, if a SCSI bus is nearly fully populated, with all disk drives in a single

RAID array, sustained read performance will be only marginally better than the same bus with

fewer drives tuned more appropriately for the load. This example benefits more from splitting the

single SCSI bus into two or more busses than from adding more drives to an already saturated

bus. When tuning the I/O of a server, you seek to find the level of redundancy that provides

optimal performance in your server’s application.

Network Interface

The key to realizing the optimal performance from your server is understanding the way in which

clients access your server. The mix of client access can vary widely from server to server, and

even from hour to hour on the same server. In some cases, clients may be requesting random,

scattered, smaller files from the server; as in a web-server. Other situations may ask the server to

retrieve large, contiguous graphic or CAD files. While still other servers will have to respond to a

PIn this paper, a flag

indicates a key point to a

performance recommendation.

I/O Performance Tuning of Compaq Servers 6

ECG044.0399

great deal of write requests. In each of these situations, tuning the performance of the server

requires a different approach. As a result, knowing the kind of load, or server mix, that clients

place on your server is key to tuning your I/O.

On most local area networks, servers are connected to clients over an Ethernet network.

Currently, there are three Ethernet specifications:

•10BASE-T provides each client with a shared resource with a maximum bandwidth of 10

Megabits per second (Mb/s) or 1 Megabyte per second (MB/s).

•100BASE-T is 10 times faster than 10BASE-T, providing 10 MB/s of bandwidth.

•Gigabit Ethernet, the newest specification, can move approximately 120 MB of data per

second; 100 times faster than the original 10BASE-T specification.

Ideally, the server should be able to deliver the full 1 MB/s, 10 MB/s, or 100 MB/s to every

network segment, depending on the NICs used.

In practice, however, on multi-client networks with unswitched hubs and repeaters each client

shares the bandwidth resource with all other clients on the segment. To overcome this limitation,

intelligent network switches enable point to point communication between nodes. When using

network switches, each port on the switch is seen as the only client on that network segment. In

this case, your network maximizes throughput because collisions are eliminated. Switches allow

greater utilization of bandwidth, however the added cost of intelligent switches may outweigh the

performance gains in smaller, less stressed network segments.

When planning or implementing your network, be aware of utilization limitations. Either

distribute network traffic between separate network segments or use intelligent switches

to eliminate packet collisions and maximize throughput.

Peripheral Component Interconnect (PCI) Bus

The PCI bus is a high-performance, 32 or 64-bit local bus that provides an interface for high-

speed transfers to peripheral components without taxing the host processor. A single 32-bit PCI

bus provides 133 MB/s of bandwidth between PCI devices and the host bus, which holds the CPU

and main memory. In order to provide greater performance and connectivity, Compaq ProLiant

servers (models 1200 to 7000) use a bridged-PCI architecture to connect multiple PCI busses

within the server. Compaq uses two different architectures to connect the two PCI busses to the

host bus: the dual-peer PCI bus and the bridged PCI bus.

In order to maintain maximum performance, Compaq recommends that you balance the

load according to the architecture in your server.

Bus Balancing in ProLiant Servers

Bridged PCI bus

In bridged PCI busses, such as the ProLiant 2500 and ProLiant 2500R, you should

populate the primary PCI bus completely before adding any adapters to the secondary

bus.

Because the secondary PCI bus shares the data path of the primary PCI bus, bus balancing is not

recommended in bridged-PCI servers. In fact, Compaq recommends that you have the primary

bus completely populated before adding cards to the secondary bus. Cards in the secondary bus

need to pass their control and data through the extra bridge chip and incur delays not only from

I/O Performance Tuning of Compaq Servers 7

ECG044.0399

the bridge chip itself, but also from any synchronization or contention with the primary bus.

Simply stated, I/O loads on the secondary bus are not handled as efficiently as equivalent loads

on the primary bus. When placing devices on the secondary bus, select the adapters with the

lightest I/O load.

133MB/s 133MB/

Primary PCI Bus

PCI Slot

Secondary PCI Bus

PCI Slot

Microprocessor

Motherboard

Chipset System

Memory

PCI

Bridge

Chip

133MB/s

Figure 2.Bridged PCI Architecture

Peer PCI bus

In Peer PCI busses, however, you should attempt to balance the I/O load between the

busses.

Since each 32-bit PCI bus can move 133 MB of data per second, making efficient use of both PCI

busses can deliver 266 MB/s of combined throughput. By balancing the I/O load evenly between

peered PCI busses, you ensure most efficient use of PCI throughput. Although evenly distributing

adapters between the two busses is a good starting point, balancing the load on the two PCI

busses requires a bit more insight into the loads generated by each type of device.

Generally, the guidelines below will deliver a balanced bus when adding controllers to your

server.

1. When installing an even multiple of network or array controllers, split the controllers

evenly between the busses. For example, if you were adding two array controllers

and two network controllers, you should put one each of the network and array

controllers in each of the PCI busses.

2. If installing an "odd" number of controllers, for example, two NICs (Network

Interface Controller) and one drive array controller, split the two network controllers

between the busses. Network controllers consume more bandwidth than array

controllers do, so it is best to split the workload between two busses if possible.

I/O Performance Tuning of Compaq Servers 8

ECG044.0399

3. Avoid putting two network controllers together in the same bus unless both busses

already have a network controller installed. Note thatSince fewer devices can lower

contention, it is generally better to have a system with one dual-port NIC in each

bus than to have two single-port NICs in each bus.

4. When adding redundant NIC pairs, place both NICs on the same bus. If the server

was to failover to the backup device the load would remain balanced.

Secondary PCI Bus

PCI Slot

Microprocessor Motherboard

Chipset

System

Memory

Primary PCI Bus

PCI Slot

266MB/s

133MB/s

Figure 3.Peer PCI Architecture

These guidelines should not be followed if one device consistently operates at a higher load. If,

for example, one particular NIC operates at or near its upper limit while 3 other NICs in the same

server remain relatively idle, you should not split the number of NICs evenly. In this case, you

should attempt to balance the loads by placing the heavily loaded card in one bus and the less

active NICs in another bus. Balancing the total load on the PCI bus, from all devices, is the key to

maximizing PCI throughput.

Table 1. PCI Bus Architectures of ProLiant servers

PCI Slot

Number Bridged PCI Bus

Systems Peered PCI Bus Systems

ProLiant 2500 ProLiant 1200 ProLiant 1600 ProLiant 3000/

ProLiant 5500 ProLiant 5000 ProLiant 6000/

ProLiant 7000 ProLiant 6500

1Secondary Secondary Secondary Primary Primary

2Secondary Secondary Secondary Primary Secondary Primary

3Secondary Secondary Secondary Primary Secondary Primary Secondary

4Primary Primary Primary Primary Secondary Primary Secondary

5Primary Primary Primary Secondary Primary Primary Secondary

6Primary Primary Primary Secondary Primary Primary Secondary

7Secondary Primary Secondary Secondary

8Secondary Primary Secondary Secondary

9Secondary

10 Secondary

11 Secondary

I/O Performance Tuning of Compaq Servers 9

ECG044.0399

PCI Bandwidth & Saturation

While balancing the busses cannot increase your maximum throughput of 133 MB/s per bus, it

can increase the potential sustained throughput of the server. By making sure that you use the

maximum bandwidth on the two busses, you can increase overall performance. When a bus is

carrying its maximum sustained throughput, the bus is said to be saturated. Once any bus has

become saturated, it becomes a limiting factor in server performance. Balanced busses saturate at

higher performance levels. Here again, the loads placed on your server will determine the

importance of a balanced bus. In general, the high-speed PCI busses in Compaq servers are less

likely to become saturated in environments where random, small-block transfers are the norm.

Operating at 33 MHz and transmitting 32 bits in parallel, small files common in web serving and

user storage are not usually on the bus long enough to cause any sustained saturation. However,

exceptionally heavy loads of small block transfers or large block transfers, common in video

streaming or CAD storage, can make a balanced bus a critical part of your server’s performance.

Compaq recommends that you always balance the loads on your PCI busses according to the

guidelines above. However, the impact that balancing will have on performance will vary

depending on the load placed on your server.

SCSI Bus

SCSI provides performance and features that have made it the interface of choice for Compaq

servers. Originally, there was SCSI, which was renamed to SCSI-1 with the advent of SCSI-2.

SCSI-1 suffered from many compatibility issues that were addressed in the next revision. At the

same time SCSI-2 clarified and established SCSI standards, it extended the performance and

functionality, both making SCSI more powerful and resolving compatibility issues. SCSI-3, the

newest standard, extends the functionality of the SCSI bus to new devices such as Fibre Channel,

SCSI-3 Parallel Interface, and the High Performance Serial Bus. Most importantly, SCSI-3 paves

the way for a higher-performance bus interface.

When referencing SCSI devices, prefixes, such as Wide, Narrow, and Fast, are used. Each of

these prefixes gives some insight to the maximum performance of the SCSI device. There are two

classes of prefixes; those that deal with the bus speed and those that deal with bus width. Table 1

summarizes and defines some common SCSI prefixes.

Table 2. SCSI prefixes

Regular This term is no longer used. Regular, or the lack of Fast or Ultra, denotes the original 5

MHz SCSI bus speed. On a narrow bus, Regular SCSI could transmit 5 MB/s.

Fast Defined in SCSI-2, the Fast protocol increases the speed of the SCSI bus to

10 MHz. On narrow busses, which transmit 1 byte per clock cycle, this gives a

maximum throughput of 10 MB.

Bus speed

Ultra The Ultra protocol, part of the SCSI-3 specification, builds on the performance of Fast

SCSI, but doubles the clock again to 20 MHz. Ultra SCSI can transmit up to 20MB/s on

a narrow bus.

Narrow The original SCSI bus is capable of transmitting 8 bits per clock cycle. The term narrow

is rarely used, but implied by the lack of the Wide prefix.

Bus width

Wide Introduced as part of the SCSI-2 specification, Wide busses allow the transmission of 2

bytes or 16 bits per clock cycle. By doubling the data bus width, the throughput of the

SCSI bus doubles. In Wide-Fast SCSI, the throughput reaches 20 MB/s; and in Wide-

Ultra SCSI, the throughput has a maximum of 40 MB/s.

I/O Performance Tuning of Compaq Servers 10

ECG044.0399

SCSI Bus Interface

Since SCSI was introduced, several specifications have been released and many new extensions

have been defined. With each subsequent release of the SCSI specification; expandability,

performance, flexibility, and compatibility have increased or improved. Currently, there are three

SCSI specifications.

SCSI-1

The original SCSI standard, approved by ANSI in 1986, defined the first SCSI bus in terms of

cabling length, signaling characteristics, commands, and transfer modes. The default (Regular)

speed for SCSI was 5 MB/s. It had an 8-bit (Narrow) parallel bus that transferred a single byte of

data with each bus cycle. “Regular” and “Narrow” conventions are no longer mentioned in the

SCSI protocol names.

SCSI-2

The second version of the SCSI standard, SCSI-2, was approved in 1990. SCSI-2 was an

extensive enhancement that defined support for many advanced features, including:

• Fast SCSI: A high-speed transfer protocol that doubles the speed of the bus to 10 MHz.

With an 8-bit data pathway, the transfer rate is 10 MB/s.

• Wide SCSI: Widens the original 8-bit SCSI bus to 16 bits to permit more data

throughput at a given signaling speed. The combination of Fast and Wide (Fast-Wide

SCSI-2) offers data transfer rates up to 20 MB/s.

• More Devices per Bus: Wide SCSI busses support 16 devices (15 drives, plus

controller) as opposed to eight with regular (Narrow) SCSI.

• Better Cables and Connectors: SCSI-2 defined a new high-density 68-pin “B” cable

and connectors.

• Active Termination: Provided more reliable termination of the bus.

In addition to these features, SCSI-2 maintained backward compatibility with all SCSI devices.

SCSI-3

SCSI-3 is a group of documents that define the implementation of SCSI protocols on different

physical layers (SCSI-3 Parallel Interface, High Performance Serial Bus, Fibre Channel, and

Serial Storage Architecture). Each physical layer has different performance characteristics and

uses different hardware. Other documents in the SCSI-3 standard are still being developed.

Currently, the SCSI-3 standard includes SCSI-2’s performance and functionality enhancements

plus:

• Ultra SCSI: Doubles the bus speed to 20 MHz and the transfer rate to 20 MB/s with an

8-bit data pathway.

• Wide-Ultra SCSI-3: Doubles the Ultra SCSI transfer rate to 40 MB/s using a 16-bit data

pathway.

• Improved Cabling: A new 68-pin “P” cable replaces the “B” cable for use with Wide

SCSI.

Compaq has extensively tested and integrated the Wide-Ultra SCSI-3 technology in Compaq

servers and storage options because it allows the highest available performance in a SCSI host

Autres manuels pour 108164-003 - ProLiant - 800

Ce manuel convient aux modèles suivants

Table des matières

Autres manuels Compaq Serveur

Compaq

Compaq 108164-003 - ProLiant - 800 Guide de démarrage rapide

Compaq

Compaq AlphaServer 1200 Manuel utilisateur

Compaq

Compaq 386746-001 - ProLiant - 1600 Guide de démarrage rapide

Compaq

Compaq ProSignia 200 Guide de démarrage rapide

Compaq

Compaq AlphaServer DS20E Manuel utilisateur

Compaq

Compaq ML330 - ProLiant - G3 Guide de référence rapide

Compaq

Compaq ML350 - ProLiant - G2 Instructions d'utilisation et de sécurité

Compaq

Compaq 1850R - ProLiant - 128 MB RAM Instructions d'utilisation et de sécurité

Compaq

Compaq T5720 - Thin Client Guide d'installation

Compaq

Compaq 108164-003 - ProLiant - 800 Guide de référence rapide

Compaq

Compaq 234664-002 - ProLiant - ML330T02 Manuel

Compaq

Compaq Evo Thin Client t20 Fiche technique

Compaq

Compaq ProLiant 5500 Instructions d'utilisation et de sécurité

Compaq

Compaq 244857-001 - TaskSmart - C4000 Model... Manuel utilisateur

Compaq

Compaq ProLiant DL380 G2 Manuel utilisateur

Compaq

Compaq 234664-002 - ProLiant - ML330T02 Instructions d'utilisation et de sécurité

Compaq

Compaq AlphaServer GS160 Manuel utilisateur

Compaq

Compaq t1000 - Terminal Thin Client PC Fiche technique

Compaq

Compaq CL380 - ProLiant - 256 MB RAM Guide de sécurité

Compaq

Compaq ProLiant 1600 Manuel

Compaq

Compaq 307560-001 - ProLiant - 2500R Manuel utilisateur

Compaq

Compaq ProLiant DL380 G2 Instructions d'utilisation et de sécurité

Compaq

Compaq ML370 - ProLiant - G3 Manuel utilisateur

Compaq

Compaq Evo Thin Client t20 Manuel utilisateur

Manuels Serveur populaires d'autres marques

HP AlphaServer ES47 Manuel utilisateur

Dell

Dell PowerEdge R410 Manuel utilisateur

PowerNAS

PowerNAS CMA Manuel utilisateur

Supero

Supero FatTwin F617R3-FT Manuel utilisateur

MSI

MSI P1-109N-L70 Manuel utilisateur

Dell

Dell PowerEdge XE9640 Manuel

Dell

Dell PS4100 Instructions de montage

EtroVISION

EtroVISION EV3151 Manuel utilisateur

NEC

NEC Express5800/T110j Manuel utilisateur

HP ProLiant Gen9 Manuel utilisateur

Dell

Dell PowerEdge 3YPMN Manuel utilisateur

iRobo

iRobo IPC2U Manuel utilisateur

Nortel

Nortel 1000 Con?guration guide Manuel utilisateur

Asus

Asus AP7500 Manuel d'utilisation et d'entretien

Avid Technology

Avid Technology AirSpeed 5000 Manuel utilisateur

HP Integrity rx2600 Guide d'installation

Milestone

Milestone Husky IVO 350T Manuel utilisateur

Planet

Planet NAS-7410 Manuel utilisateur