DROBO PERFORMANCE STATS

Transcription

1 DROBO PERFORMANCE STATS By StorageNerve 11/30/

2 Drobo Performance Stats Some discussions on twitter last week triggered the topic of performance relating to the Drobo s. This is the 5 th consecutive post on Drobo Series of products. To read other Drobo related posts: Drobo S and DroboElite Introduced 11/23/2009 Some very interesting articles on Drobo S and DroboElite The Drobo Math I totally love my Drobo but Here are some performance stats collected with running Drobo as a direct attached storage and using some benchmarking tools to compile these results. All the performance stats are collected using different criteria s that can affect the performance of the Drobo. Also used various connection methods including USB and Firewire to obtain these stats. The entire series of tests have been performed using Mac OSX host with either USB attached or Firewire attached to the Drobo. These results are limited to the Drobo and cannot be compared to the Drobo Pro or Drobo Elite or Drobo S. The test were carried out with using various combination of drives, rebuilt data protection, best-case scenario, worst-case scenario, 1 drive, 2 drives, 4 drives, different drive cache & capacity

3 Test Ingredients Drive 1: Capacity: 1TB Cache: 32MB Type: SATA Interface Speed: 3Gb/s Host to Drive: 111 MB/s Manufacturer: Western Digital Drive 2: Capacity: 1 TB Cache: 32MB Type: SATA Interface Speed: 3Gb/s Host to Drive: 111 MB/s Manufacturer: Western Digital Drive 3: Capacity: 640 GB Cache: 32MB Type: SATA Interface Speed: 3Gb/s Host to Drive: 108 MB/s Manufacturer: Western Digital Drive 4: Capacity: 500 GB Cache: 8MB Type: SATA Interface Speed: 3Gb/s Host to Drive: 108 MB/s Manufacturer: Western Digital - 3 -

4 Cases Case 1: USB Connect, 4 drives installed, perfect case scenario Case 2: USB Connect, 2 drive installed, data rebuild in progress Case 3: USB Connect, 1 drive installed, no data protection enabled Case 4: USB Connect, 2 x 1TB drives installed, data protection enabled Case 5: Firewire Connect, 4 drives installed, perfect case scenario Case 6: Firewire Connect, 2 drive installed, data rebuild in progress Case 7: Firewire Connect, 1 drive installed, no data protection enabled Case 8: Firewire Connect, 2 x 1TB drives installed, data protection enabled Host Information USB 2.0 Connection from Host to Drobo Connected to a Mac book Pro OSX No additional overhead or processes on the laptop, minimum impact Tested at the home office labs Drobo Information Drobo Firmware: Dashboard: Volume Size: 4 TB Actual Usable Storage: 1.93 TB Drive Slots: Slot 0: Drive 1 Slot 1: Drive 2 Slot 2: Drive 3 Slot 3: Drive 4-4 -

5 USB Performance Test Results below - 5 -

6 Case 1: 4TB of storage volume, 4 drives installed, USB mounted Stats with file size 4 GB Disk Read/Write - 6 -

7 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write - 7 -

8 Results: This is a best-case scenario, with full data protection, 4 drives, and no additional overhead on the Drobo. For a 4 GB file transfer, we managed to get a consist Read transactions rate of about 28 MB/sec, while the write transaction rate for a large 4 GB file was about 25 MB/sec for USB connected Drobo. Though throughout the 4 GB read/write operation, our I/O varied between 20 MB/sec to 32 MB/sec, which is really the max speeds the Drobo will obtain through the USB connections. For a 128 MB file transfer, we managed to get a consist Read transaction rate of about 28 MB/sec, while the write transaction rate for a small file was about 27 MB/sec. Our I/O transaction rate did not fluctuate a lot in this case. With various frame size sweeps, our I/O for read and writes stayed pretty consistent between 24 MB/sec to 28 MB/sec. Given this is a best-case scenario; we should not exceed an I/O rate beyond 32 MB/sec for the Drobo. Going forward with different scenarios in picture, we should see this I/O transaction rate number vary a bit

9 Case 2: 4TB of storage volume, 2 drives installed, USB mounted Performance stats during data rebuilt for data protection Stats with file size 4 GB Disk Read/Write USB mounted, 4 TB - 9 -

10 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

11 Results: This is a kind of a worst-case scenario, since we have two drives in the Drobo and it is going through a data protection rebuild now, causing additional overhead on the Drobo relating to I/O Transaction. For a 4 GB file transfer, we managed to get fluctuating Read/write transactions rate 10 MB/sec to 30 MB/sec, while the average read/write transaction rate for a large 4 GB file about 23 MB/sec. For a 128 MB file transfer, we managed to get consistent Read transaction rate of about 26 MB/sec, while the write transaction rate fluctuated between 5 MB/sec to 25 MB/sec for a small file. Our I/O transaction rate fluctuated a lot in this case. With various frame size sweeps, our I/O for read and writes stayed pretty consistent at around 20 MB/sec. Given this is one of the worst-case scenarios; we shouldn t see a worst performance than shown above

12 Case 3: 4TB of storage volume, 1 drives installed, USB mounted No data protection. In short no BeyondRAID technology with one drive installed Stats with file size 4GB Disk Read/Write

13 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

14 Results: For USB Connection, here are the results. This is a kind of a worst case scenario, since we have one drive in the Drobo and it does not have any data protection, in short the drive failure can result into a data loss scenario, while this case is similar to the performance you may get out of a standalone disk drive mounted through the USB port. For a 4 GB file transfer, we managed to get fluctuating write transactions rate 3 MB/sec to 32 MB/sec, while the average write transaction rate for a large 4 GB file is about 25 MB/sec. For a 4 GB file transfer, we managed to get fluctuating read transactions rate 20 MB/sec to 30 MB/sec, while the average read transaction rate for a large 4 GB file about 28 MB/sec. For a 128 MB file transfer, we managed to get a consistent Read transaction rate of about 28 MB/sec, while the write transaction rate fluctuated between 10 MB/sec to 25 MB/sec for a small file. With various frame size sweeps, our I/O for read transactions stayed pretty consistent at around 26 MB/sec while the writes fluctuated between 17 MB/sec to 23 MB/sec

15 Case 4: 4TB of storage volume, 2 drives installed: 1 TB and 1 TB, USB mounted Data Protection enabled Stats with file size 4 GB Disk Read/Write

16 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

17 Results: For USB Connection, here are the results. This is a kind of a good case scenario, since we have two drives (similar size, make, model, cache) in the Drobo and it does have data protection enabled. For a 4 GB file transfer, we managed to get consistent write transactions rate of 27 MB/sec, while the read transactions stayed pretty consistent at 30 MB/sec. Interesting enough, for a 128 MB file, we got a similar performance results as that compared with 4 GB file size. With various frame size sweeps, our I/O for read transactions stayed pretty consistent at around 26 MB/sec while the writes fluctuated between 20 MB/sec to 24 MB/sec. This means one thing, use your Drobo with all 4 drives if USB mounted. You may get worst performances with less number of spindles (drives) or a standalone drive

18 Case 5 through Case 8 using Firewire connections Host Information Firewire Connection from Host to Drobo Connected to a Mac book Pro OSX No additional overhead or processes on the laptop, minimum impact Tested at the home office labs Drobo Information Drobo Firmware: Dashboard: Volume Size: 4 TB Actual Usable Storage: 1.93 TB Drive Slots: Slot 0: Drive 1 Slot 1: Drive 2 Slot 2: Drive 3 Slot 3: Drive

19 Firewire Performance Test Results below

20 Case 5: 4TB of storage volume, 4 drives installed: 1TB, 1 TB, 640 MB, 500 MB, Firewire mounted Data Protection enabled Stats with file size 4 GB Disk Read/Write

21 Picture with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

22 Results: For Firewire Connection, here are the results. This is a best-case scenario, with full data protection, 4 drives, and no additional overhead on the Drobo. For a 4 GB file transfer, we managed to get a fluctuating Read transactions rate between 35 MB/sec to 50 MB/sec, while the write transaction rate for a large 4 GB file were between 25 MB/sec to 35 MB/sec. Drobo with Firewire connections CAP out at 52MB/sec, which is about 20MB/sec more than USB on the same Drobo unit. For a 128 MB file transfer, we managed to get a consist Read transaction rate of about 46 MB/sec, while the write transaction rate for a small file was about 35 MB/sec. With various frame size sweeps, our I/O for read and write fluctuated with lower performance with smaller frame size. Given this is a best case, scenario; we should not exceed an I/O rate beyond 52 MB/sec for the Drobo. Going forward with different scenarios here, we should see this I/O transaction rate number vary a bit. One thing I learned about Firewire today was the I/O rates are not consistent through out file transfers and they tend to fall and cap out again at max speed, something very interesting compared to the USB

23 Case 6: 4TB of storage volume, 2 drives installed, Firewire mounted Performance stats during data rebuilt for data protection Stats with file size 4 GB Disk Read/Write

24 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

25 Results: This is a kind of a worst-case scenario, since we have two drives in the Drobo and it is going through a data protection rebuild now, causing additional overhead on the Drobo relating to I/O Transaction. For a 4 GB file transfer, we managed to get fluctuating Read transactions rate 15 MB/sec to 50 MB/sec, while the average read transaction rate for a large 4 GB file about 39 MB/sec. For a 4 GB file transfer, we managed to get fluctuating write transactions rate 10 MB/sec to 37 MB/sec, while the average read transaction rate for a large 4 GB file about 32 MB/sec. For a 128 MB file transfer, the results were very similar, heavy read fluctuations. With various frame size sweeps, our I/O for read and writes stayed pretty consistent for smaller frame size while for larger the I/O transactions reduced substantially. Given this is one of the worst-case scenarios; we shouldn t see a worst performance than shown above

26 Case 7: 4TB of storage volume, 1 drives installed, Firewire mounted No data protection. In short no BeyondRAID technology with one drive installed Stats with file size 4 GB Disk Read/Write

27 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

28 Results: Very interesting, these results are very similar to Case 5, where we had all 4 drives in the Drobo. Does this mean, the fully populated firewire connected Drobo will give you almost the same performance as a single drive drobo unit

29 Case 8: 4TB of storage volume, 2 drive installed: 1 TB and 1 TB, Firewire mounted Data Protection enabled Stats with file size 4 GB Disk Read/Write

30 Stats with file size 128 MB Disk Read/Write Stats with random I/O xx MB/sec Disk Read/Write

31 Results: Very interesting, these results are very similar to Case 6 and Case 7, where we had all 4 drives and 1 drives in the Drobo. Does this mean, the fully populated firewire connected Drobo will give you almost the same performance as a single drive or two drive drobo unit

32 Some other results Stats Host Connection: Firewire Drives: Fully populated in all 4 slots Host: MacBookPro, Mac OSX Firewire performance

33 Host Connection: USB Drives: Fully populated in all 4 slots Host: MacBookPro, Mac OSX USB Performance

34 Final Results: So with the above 4 scenarios with using the USB connection and the rest of the 4 with using the Firewire connections, we have our results listed above. Based on these stats, it is highly recommended to use the Firewire connections compared to the USB connections, since we have seen pretty stable results with using the Firewire. Firewire seems to CAP out at 52 MB/sec while USB does it at 32 MB/sec. For better through put, firewire seems to do the magic. With these transfer rates, it is recommended to use the Drobo where you do not plane to exceed your typical I/O transactions above 50 MB/sec or the Drobo could start having some serious effects. Also the Drobo performance hits a bottleneck during drive upgrades and drive replacements upon a drive failure. It may be recommended to perform those functions during times when you do not plan to use the Drobo. If you are also using the Drobo with large file sizes stored on the Drobo, consider using the Firewire ports compared to the USB port and fully loaded Drobo compared to a 2 or 3 drive populated Drobo for better performance. Summary Results: Large File 4GB Best Case Worst Case Read Write Read Write USB Firewire Small File 128 MB Best Case Worst Case Read Write Read Write USB Firewire

35 For Large File 4GB, USB to Firewire comparisons comparisons,, Best Case and Worst Case Scenario s, I/O Transactions MB/Sec comparisons,, Best Cast and Worst Case For small file 128 MB,, USB to Firewire comparisons Scenario s, I/O Transactions MB/Sec