DELL EMC Poweredge R750 Server Review

Contents of Articles:

1. Dell R750 Specifications. Comparison of Dell R750 server with Dell R740
   1. Cooling system 
2. Dell EMC PowerEdge R750 Architecture and Design
   1. Disk subsystem
   2. Scalability and Network
3. Dell EMC PowerEdge R750 performance in real tests
   1. SQL Server Efficiency
   2. Sysbench MySQL Efficiency
   3. TPS indicators
4. Dell R750 options
5. Conclusion

Dell R750 Specifications. Comparison of Dell R750 server with Dell R740

The Dell EMC PowerEdge R750 is a dual-socket rack server in a 2U form factor, making it an ideal choice for enterprise-class environments. It's known for its compact design, which efficiently utilizes rack or closet space. In this discussion of its technical specifications and capabilities, we will also draw comparisons with the Dell R740 server, which we previously reviewed.

According to the table, the internal layout of components in the R750 has become more dense, which led to the possibility to install more RAM sticks.

Cooling system

The cooling system has also been upgraded. The air flows are distributed more evenly in the R750. This reduces the number of “hot spots”.

After modernization (three levels, five blades), the fans became more powerful and reliable.

Moreover, Multi-Vector Cooling (MVC) 2.0 technology was implemented in the R750. The functions of this technology are:

• analysis of air flow temperature at the inlet and outlet,
• processing of received data,
• data transfer to the user for fine-tuning cooling.

This is possible if there is embedded automation, which is triggered when the memory, graphics accelerators, processors themselves, or other components become critically overheated.

Left fan from R740, right fan from R750

For high-density environments there is an option – DLC (Direct Liquid Cooling). The R750 has an embedded leak detection system, which is extremely necessary, since liquid cooling can lead to a short circuit and even a fire. This technology immediately performs the following actions:

• de-energize the system,
• shut off the coolant flow,
• send a notification to the system administrator.

Other changes:

• PCIe 4.0 and upgrade of existing technologies.
• Modern Intel Xeon Scalable 3 processors.
• Improved disk subsystem.
• Increased memory speed.

Dell EMC PowerEdge R750 Architecture and Design

Server design does not change much from one generation to another, since, first of all, all server components have a functional purpose.

However, it is worth noting such an element as the bezel (it is purchased separately). Being an additional design element for the front part of the server, the bezel has certain functionality – using the front bezel you can lock front interfaces, disk cages, etc.

Next, let's consider the architecture. The front panel includes:

• Basic power button.
• USB type A and Micro-USB for control via iDRAC.
• Status indicators responsible for visual identification of emergency situations.

Disk subsystem

R750 provides 4 options for disk baskets on the front:

• Up to 24 2.5" SAS/SATA/NVMe (HDD/SSD) up to 368.84 TB.
• Up to 16 x 2.5" SAS/SATA/NVMe (HDD/SSD) up to 245.76 TB.
• Up to 8 2.5" NVMe (SSD) up to 122.88 TB.
• Up to 12 3.5" SAS/SATA (HDD/SSD) up to 192 TB.

There are also 2 options for the rear compartments:

• Up to 4 x 2.5" SAS/SATA/NVMe (HDD/SSD) 61.44 TB (max.)
• Up to 2 x 2.5" SAS/SATA/NVMe (HDD/SSD) 30.72 TB (max.)

The R750 has one important feature – support for PCIe 4.0 drives and the U.2 form factor. This feature allows you to install modern drives that are characterized by high reading and recording speeds. Example of a possible drive – SSD Intel U.2 D7-P5510 3.84 TB:

• up to 3400 Mb/s recording,
• up to 6500 MB/s reading,
• 170,000 IOPS when recording 4KB files with a queue depth of 32.

R750 has another additional feature – new BOSS-S2 boards with hot plugging (it is provided through a special cassette on the back side). Relevant maintenance is carried out very easily and quickly thanks to this solution.

Scalability and Network

Scalability – availability of 8 PCIe 4.0 slots (six of which are x16), as well as new optional SNAP I/O module. This module divides the x16 slot into two x8. Using the SNAP module, the network card can simultaneously interact with two processors.

Network – 2 embedded Gigabit ports 8P8C and OCP 3.0. Now users have the opportunity to use several ports at once (no need to choose between 2 data speed options).

Dell EMC PowerEdge R750 performance in real tests

We will consider a very powerful platform for testing:

• CPU — 2 x Intel Xeon Scalable (3rd generation). Model 8380;
• Drives — 8 x Intel P5510 3.84TB Gen4 SSD;
• RAM – 32 x 32GB DDR4 3200 MT/s;
• CentOS 8.2;
• ESXi 7.0u1.

SQL Server Efficiency

Each SQL Server virtual machine includes the following components:

• 2 virtual disks –100 GB for boot and 500 GB for database and log files;
• 64 GB of DRAM;
• 16 vCPU;
• LSI Logic SAS SCSI controller.

SQL tests are conducted in order to study the response time.

SQL Server configuration for the test (for each VM):

1. Windows Server 2012 R2;
2. Storage size: 600 GB allocated, 500 GB occupied;

3. SQL Server 2014:

   • DB size: 1500;
   • Virtual client loads: 15000;
   • RAM buffer: 48 GB;

The test lasts 3 hours:

• 2.5 hours of preliminary preparation;
• 30-minute sample period.

For SQL Server, the considered configuration showed a delay of 1 ms for the entire testing time with eight VMs.

Sysbench MySQL Efficiency

Each Sysbench VM includes the following components:

• Three virtual disks:

  1. with pre-embedded database (~447 GB);
  2. to download (~92 GB);
  3. for the tested database (270 GB).
• 60 GB of DRAM;
• 16 vCPU;
• LSI Logic SAS SCSI controller.

Sysbench MySQL test is carried out in order to measure:

• average data transfer rate,
• average delay,
• average delay in the 99th percentile (p99-metric).

Sysbench configuration for the test (for each VM):

1. Percona XtraDB 5.5.30-rel30.1;
2. CentOS 6.3 64-bit;

3. Database tables – 100:

   • DB size: 10,000,000,
   • RAM buffer: 24 GB,
   • Database streams: 32.

The test lasts 3 hours:

• 2 hours of preliminary preparation of 32 streams;
• 1 hour – 32 streams.

TPS indicators

Sysbench OLTP measured a score of 29174 TPS for 8 VMs (1 VM – range from 3631 to 3665 TPS). 16 VMs – 26838 TPS (1 VM – range from 1662 to 1690 TPS).

With increasing loads, performance naturally decreases, since there is an oversaturation point for each platform. However, it is worth noting that the new 8380 Intel Xeon Scalable 3 processors provide a high level of efficiency. They also have a certain reserve.

Average delay:

• The cumulative indicator for 8 VMs is 8.77 ms (each VM is from 8.73 ms to 8.81 ms).
• The cumulative indicator for 16 VMs is 19.1 ms (each VM - from 18.87 ms to 19.24 ms).

In the worst case – the 8VM delay was 15.2 ms, the 16VM delay was 35.4 ms.

Dell R750 options

The Dell R750 server has two branches: Dell R750xa and Dell R750xs. These models are similar to the Dell R750, but have certain distinctive features, as they were originally created to perform other tasks.

The table below shows the results of the comparative analysis:

Conclusion

Thus, Dell EMC PowerEdge R740 is the most popular and reliable Dell server. They have a very high level of performance, as well as a huge potential. Considering the fact that the R740 still copes well with all necessary tasks, the R750 has been modified and improved in many ways. Great attention was paid to details, which made the R750 more reliable and suitable for a wide range of tasks.

Dell

Dell PowerEdge R740 8LFF

• 2U (rackmount)
• up to 2 Xeon Scalable
• up to 3072 GB (24 x DDR4)
• 8LFF Bay 3.5" (Hot Swap)
• 2 x PSU (Hot Plug)

Configure

Dell

Dell PowerEdge R740 8SFF

• 2U (rackmount)
• up to 2 Xeon Scalable
• up to 3072 GB (24 x DDR4)
• 8SFF Bay 2.5" (Hot Swap)
• 2 x PSU (Hot Plug)

Configure

Dell

Dell PowerEdge R740 16SFF

• 2U (rackmount)
• up to 2 Xeon Scalable
• up to 3072 GB (24 x DDR4)
• 16SFF Bay 2.5" (Hot Swap)
• 2 x PSU (Hot Plug)

Configure