Elliott C. Back: Internet & Technology

Synology DS1511+ NAS Review

Posted in Computers & Technology, Hardware, NAS by Elliott Back on April 19th, 2011.

In this post, I’ll be reviewing a brand new Synology DiskStation DS1511+ NAS equipped with five Hitachi Deskstar 2TB 5K3000 drives configured in RAID5. For comparison, I’ve also written about the Gen 1 Drobo’s performance as a NAS before (it tops out around 20MB/s), and own two of them at home. While the Drobos allow you to build mix-and-match RAID arrays, they are slow, take forever to rebuild, noisy, and hot. I am hoping the DS1511+ will remedy all of these issues.

Read more about the DS1511+ specs here

Network Base Configuration

The Synology NAS is using default MTU of 1500, connected to a Gigabit Ethernet Switch on LAN2. Testing with iperf shows a good gigabit connection between my PC and the NAS of around 885Mb/s:

Big_Bug> iperf -s
Server listening on TCP port 5001
TCP window size: 85.3 KByte (default)
[ ID] Interval Transfer Bandwidth
[ 7] 0.0-20.0 sec 2.05 GBytes 882 Mbits/sec
[ 6] 0.0-30.0 sec 3.09 GBytes 885 Mbits/sec

In megabytes per second, we can transfer 110.625 MB/s. As you will see, this is actually slightly lower than the performance of the RAID array.

The Hard Drives

How fast are the triple-platter 2TB deskstar 5K3000s in RAID5? It can do a very reasonable 125 MB/s in unbuffered pure-disk performance:

Big_Bug> hdparm -t /dev/sda
Timing buffered disk reads: 374 MB in 3.01 seconds = 124.22 MB/sec

Benchmarking File Copy from Windows

To test how fast I can transfer from my PC to the NAS, I’ve created a 4GB binary file:

C:\Users\Elliott Bäck\Desktop>ls -l test.file
-rw-rw-rw- 1 Elliott Bäck 0 4693544330 2011-04-19 20:00 test.file

Copying this file in Windows 7’s explorer took just 50.5 seconds. Doing the math, this gives us an average write rate of 88.63 MB/s. How fast can we copy it back? It took 71.6 seconds, for an average read rate of 62.51 MB/s. Both of these number are going to be constrained by how fast my desktop PC’s Intel SSD can read/write. I also tested using Java and writing a RandomAccessFile with a ByteBuffer, which achieved 95MB/s write and 97MB/s read on a 1GB file.

Reliability & Temperature

You just need to open up the storage manager on the Synology DS1511+ NAS to see what a beauty it is, giving you a full SMART status readout on all your physical drives, as well as their temperatures. Even after running through my benchmarking, the drives were only 34° C warm:


At nearly $900 for the NAS itself without drives, it’s pricey. But plugged into a Gigabit ethernet, the DS1511+ from Synology is also fast, cool, and quiet; the three things you want most from a NAS. Featurewise, it has a glorious UI, media servers built in (which I don’t use) and expandibility from 5 to a maximum of 15 drives. I anticipate phasing out my Drobos, with their proprietary technology, for the Synology NAS, which runs on open-source plain-vanilla linux.

configure: error: no acceptable C compiler found in $PATH

Posted in Code, Computers & Technology, Linux by Elliott Back on September 14th, 2008.

If you get the following command when trying to build a package from source on linux (Fedora 8 in my case), chances are you don’t have GCC installed:

configure: error: no acceptable C compiler found in $PATH
See `config.log' for more details.

The solution is simple, run one of the following commands to install a C compiler:

CentOS: yum -y install gcc
Fedora: up2date -i gcc

For me, this installed a few additional helper packages to get me started compiling C-code:

 gcc                 x86_64      4.1.2-33             fedora              5.3 M
Installing for dependencies:
 cpp                 x86_64      4.1.2-33             fedora              2.9 M
 glibc-devel         x86_64      2.7-2                fedora              2.4 M
 glibc-headers       x86_64      2.7-2                fedora              599 k
 kernel-headers      x86_64      updates-newkey      746 k

Apple’s 13-inch Macbook Air Sucks

Posted in Apple, Hardware by Elliott Back on January 16th, 2008.

Today at the Macworld 2008 Expo, Steve Jobs released a new version of the Macbook called the Macbook Air. Unlike last year’s iPhone announcement, the response to the Air was negative. The price of Apple’s stock today dropped 9.02% to close at $169.04 and $163.01 in after-hours trading:


If you’re interested in the Macbook Air, check out these specifications from the Apple Store. For $1799, you get a 0.76 inch thick, 3.0 pound notebook with a 13.3 inch backlit widescreen display, 1.6 GHz Core2 Duo processor, iSight camera, backlit keyboard, and multi-touch trackpad. It has a single USB 2 slot and a single micro-DVI slot and headphone jack via a door on the side. Wirelessly, it supports 802.11n and Bluetooth 2.1/EDR. It has no optical drive natively, and comes with a wimpy 80GB 4200 RPM hard disk. A 1.8 GHz processor and a 64GB solid-state drive (SSD) will cost $3,098.


I have to agree with Michael Arrington of Techcrunch that the laptop, even as a premium option, is grossly overpriced and underpowered. A slightly heavier, but significantly more powerful Sony Vaio (40% faster CPU, 30% faster hard disk, more ports, fingerprint sensor, nvidia graphics, twice as much hard disk space, slightly thicker, slightly heavier, same height and width) can be bought for $1800. If you go to Dell, you can configure their 13.3-inch widescreen XPS M1330 with an SSD drive and a few upgrades for just $2,404, a significant savings over Apple’s price.

It’s interesting that Kineda and Paul both point out seriously problems with the new Macbook (it’s wimpy, overpriced, and full of proprietary non-replaceable, non-upgradable parts) but still cheer it on. Paul says,

News flash to Devin people don’t buy ultraportable notebooks for their workstation-like performance. Enough said. Do I want one? Hell yes.

But, it’s Daring Fireball who finally gets to the bottom of the Macbook Air, and why it sucks. It just doesn’t make the right design choice! Thinner is not the same as smaller; we want a 12″ or 11″ or 10″ model, both smaller in form factor and thinner and lighter to boot:

I’d have rather seen a smaller footprint, a la the old 12-inch PowerBook G4 — something just exactly as wide as a full keyboard. I’d prefer to sacrifice screen size on the notebook in exchange for an even smaller machine.

Update: Did you know that five years ago, Sony made the Vaio X505, a laptop .8″ thick? Pwnt, Apple. That’s all I can say!

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