Friday, 29 April 2016

Analysing .NET code dependencies–Overview

How can you tell if modules/components in your application are loosely-coupled between each other, and tightly cohesive internally? You could read the code line-by-line, but that becomes difficult once the codebase becomes large.

It can be very valuable to be able to visualise the the dependencies between the various components that make up your application – both at the class and module/assembly level. These tools analyse code, either by parsing the source code, or by analysing the compiled assemblies to produce various summaries and reports about the state of the code.

I’m planning to spend a bit of time in future blog posts reviewing a number of these tools that can help with this analysis, including:

I’m also interested to hear what you use. Let me know in the comments of your experiences with these or other tools I haven’t mentioned.

Monday, 11 April 2016

My new Dell XPS 15 laptop

My birthday has come early this year. I've finally bought a new laptop! It wasn’t the cheapest either, so I think that will cover a couple more birthdays in the future too Smile

I'd been evaluating a number of different manufacturers and models, and eventually went with a Dell XPS 15 (9550). I'd had a pretty good run with my old XPS 1645 and that counted in the XPS 15's favour.

I bought the 1645 in 2010, so I was expecting to buy something that represented 6 years of technology improvements. So far I think the 15 delivers that.

  • 16GB DDR4
  • 512GB SSD (PCIe)
  • 4K Ultra HD (3840 x 2160) touch display

Modifications

Out of the box, the top row of the keyboard defaults to the feature keys. I make use of the Function keys (F1, F2, etc) much more than I'd use the feature keys (Mute, Volume Up/Down, etc) so I went into the UEFI firmware settings and changed that to default to function keys.

Here’s a comparison of the keyboards of the 1645 and 15 (the shiny strip above the main keyboard on the 1645 has the feature keys). Obviously fashions change too – from glossy/shiny to matte.

XPS 1645 KeyboardXPS 15 keyboard

I HATE touchpads that simulate a mouse click with a single tap. Maybe it's my hands but I find I end up 'clicking' a lot more than I intended. So it's another thing I try to disable if possible. On the 1645 this was done through the Synaptics touchpad driver, but that isn't present on the 15. Instead it turns out that's a setting provided by Windows itself.

Windows 10 Touchpad settings

Old and new comparison

XPS 15 and 1645 closedXPS 15 and 1645 open

Here’s the 15 sitting on top of the 1645, to show it’s slightly smaller.

View from above of XPS 15 sitting on top of 1645

Side views show the 15 is a fair bit slimmer. The 1645 comes with VGA, HDMI and DisplayPort ports – the 15 just has a single HDMI, but you can get an external adapter with a second HDMI and VGA (as well as extra USB and Ethernet). No DVD drive in the 15 either!

XPS 15 and 1645 right side comparisonXPS 15 and 1645 - left side comparison

The rubber feet of the 1645 fell off a while ago – both the ones on the base of the laptop and the ones fixed to the battery bar. The 15 has two rubber strips. Time will tell if they last longer.

XPS 1645 underneath - worn feetXPS 15 - underneath showing rubber feet strips

My 1645 weighs 3.065kg. I’m pleased to see the 15 weighs only 2.040kg. (For those days when I need to carry it around, my back is also pleased!)

XPS 1645 Weight - 3.065KGXPS 15 2.040kg

It’s not easy to show the difference in displays, but this gives you a bit of an idea of the 4K display of the 15 next to the standard 1080 of the 1645. It doesn’t show up here, but the 1645 screen also got quite scratched over the years from rubbing against the keyboard. Probably made worse from the extra rubber pads falling off that should have prevented this. I’m looking into getting a protective cloth for the new laptop to try and reduce the chance of that happening again.
Comparing the displays of 15 and 1645

And check out the disk performance – almost 10x faster with the PCIe SSD – nice!

HDTune Benchmark Crucial CT512MX1 SSD - Average 111 MB/secHDTune Benchmark NVMe THNSN5512GPU7_NV - Average 897 MB/sec

Finally, I’d forgotten what it was like to have a battery that holds a decent amount of charge (the 1645 might say it has 1:45 left, but that’s pretty optimistic). I can sit on the sofa with the XPS 15 and it lasts the whole evening. Wow Smile

dell xps 1645 batteryDell XPS 15 Battery

Monday, 28 March 2016

Installing future SQL Server updates with confidence

Great to read that Microsoft are now making the “cumulative update” packages ‘recommended’ installs, and the updates themselves will be easier to obtain - no longer requiring a email address to download directly, and also being listed in Windows Update Catalog (and maybe in the future as an optional update on Microsoft Update).

As a developer, I’ve often installed the latest CU (cumulative update) just because I like to be current on my own PC – but I’ve traditionally been more conservative with production SQL Servers that I’ve had to look after over the years. In the latter case I’ve installed the latest service pack, but only added a CU if it seemed likely to address any issue we might be having at the time.

With this change, now pushing out the latest CU can be done with more confidence and probably should be considered part of maintaining your SQL Server infrastructure. Quoting from the above article:

You should plan to install a CU with the same level of confidence you plan to install SPs (Service Packs) as they are released. This is because CU’s are certified and tested to the level of SP’s.

A few years back I remember thinking that the SQL Server team had really set the standard for releasing regular updates for their products (especially compared to the lack of updates at the time to fix problems with older versions of Visual Studio 2005/2008). Since then the VS team have upped their game, and now they are pushing new major servicing updates out around every quarter. That doesn’t include out-of-band updates to VS extensions that are done more frequently.

So it’s great to see the SQL Server team stepping up the pace another notch.

Tuesday, 15 March 2016

How I first heard about Lean

A quick shout-out to Flinders Medical Centre’s Redesigning Care. They implemented Lean a few years ago to improve how their hospital functioned. After hearing about what Lean was and what they were doing, I then discovered that Lean had been applied to developing software too.

If you’re interested in learning more about Lean in a healthcare setting, contact them via their webpage, or check out their overview video on YouTube

Friday, 26 February 2016

Laptop comparisons

So after a bit more research, I’ve come up with a shortlist of laptops to consider. Most vendors (with the exception of HP and Microsoft) give you quite a few options to customise during the order process. For my own reference, I’ve also included the specs of my current laptop – the Dell XPS 1645 – to contrast how hardware has progressed over the last 5-6 years.

My mandatory minimum requirements:

  • i7 CPU
  • 8GB memory
  • 512GB SSD
  • Touch screen
  • Lighter than 3Kg

Nice to haves:

  • Xeon CPU
  • 16GB memory
  • PCIe SSD
Laptop feature comparison
Dell XPS 1645 (Circa 2010) Dell XPS 13(9350) Dell XPS 15 (9550) Dell Latitude E7450

HP ZBook Studio 15 E3 Mobile Workstation

ThinkPad X1 Yoga - Core i7

Microsoft Surface Book

CPU Core I7-820QM Processor (1.73GHz) i7-6500U (up to 3.1 GHz) i7-6700HQ Quad Core (up to 3.5 GHz) i7-5600U Processor (Dual Core, 2.6GHz, 15W) Xeon® E3-1505M v5 (2.80 GHz, up to 3.70 GHz), 4 cores)

Intel Core i7-6600U Processor (up to 3.40GHz)

i7-6600U
(2.6 up to 3.4 GHz)

Cache 8MB L3 4M 6M 4M 8 MB

4MB

4 MB

Memory 8GB Dual-channel 1333MHz DDR3 SDRAM (2 x 4GB) 8GB LPDDR3 1866MHz 16GB Dual Channel DDR4 2133Mhz (8GBx2) 8GB (1x8GB) 1600MHz DDR3L 8 GB DDR4-2133 (1 x 8 GB) 16GB LPDDR3 SDRAM 1866MHz 16GB LPDDR3
Storage 500GB 7200RPM SATA Hard Drive 256GB PCIe Solid State Drive 512GB PCIe Solid State Drive 256GB (SATA3) 256 GB HP Z Turbo Drive PCIe SSD

512GB Solid State Drive, PCIe-NVMe

512GB SSD
Video Video Card -ATI Mobility RADEON(R) HD 4670 - 1GB

Intel(R) HD Graphics 520

NVIDIA® GeForce® GTX 960M with 2GB GDDR5

Intel® Integrated HD Graphics 5500

NVIDIA® Quadro® M1000M (2 GB dedicated GDDR5)

Intel HD Graphics 520

Intel HD Graphics 520
+ Nvidia GeForce 940M GPU with 1 GB of memory

Display 15.6 Full High Definition(1080p)
1920x1080
13.3 inch QHD+ (3200 x 1800) InfinityEdge touch 15.6" 4K Ultra HD (3840 x 2160) InfinityEdge touch 14.0 FHD (1920x1080) 15.6" diagonal FHD UWVA IPS anti-glare LED-backlit (1920 x 1080)

14" FHD (1920x1080), IPS, 10-point Multi-Touch

13.5” PixelSense™  3000 x 2000 (267 PPI) 10 point multi-touch
Network Wireless Network Card -Intel(R) WiFi Link 5300 (802.11a/g/n) Half Mini-c DW1820A 2x2 802.11ac 2.4/5GHz + Bluetooth4.1 DW1830 3x3 802.11ac 2.4/5GHz + Bluetooth 4.1 Intel Dual Band Wireless-AC 7265AC 802.11ac/a/b/g/n 2x2 + Bluetooth 4.0 LE Intel® Dual Band Wireless-AC 8260 802.11 a/b/g/n/ac (2x2) Wi-Fi and Bluetooth® 4.0 combo Intel Dual Band Wireless-AC 8260, 2x2, Wi-Fi + Bluetooth 4.1, vPro

802.11ac Wi-Fi wireless networking; IEEE 802.11a/b/g/n compatible
Bluetooth 4.0

Battery 9-cell (85WHr) Lithium Ion 56WHr Integrated Battery 84Whr battery 4-cell 52 Whr Lithium Polymer 4-cell 64 WHr Li-ion prismatic

4 Cell Li-Polymer Battery 52Wh

12 hour
Weight 3.06Kg 1.29kg 2kg 1.56Kg 2Kg 1.27kg+ 1.516 Kg
Dimensions (W x D x H) 380 x 260 x ? 304 x 200 x 15 357 x 235 x 17

337 x 232 x 20

375 x 255 x 18 333 x 229 x 17 232 x 312 x 23
Service 3-Year Premier Service 3Yr ProSupport : Next Business Day Onsite Service 3Yr ProSupport : Next Business Day Onsite Service 3 Yrs Next Business Day Onsite Service 3 years standard parts, labour and on-site limited warranty 3Y On-site NBD upgrade from 1Y Depot/CCI 2-year hardware warranty
Price (as at 25th Feb 2016) $2,100 (as at 2010) $2,879 $3,379 $4,441.80 $5,481 $4,118.51 $4,199

Notes

  • Where choice was offered, maximum CPU and memory selected
  • All prices in Australian dollars, including GST. Enterprise agreements or other arrangements/discounts/specials might give better prices.
  • Enterprise and/or special business programs may offer additional hardware choices/customisations.
  • Where offered, 3 year support was chosen
  • No Office subscription was included
  • Windows 10 Pro 64bit

Thoughts

I think I’ll forget about a Xeon CPU - can’t justify the premium price. Maybe one day!

Most of these devices have built-in batteries, so the option of buying a spare battery (like I did with my 1645) simply doesn’t exist these days.

Looking at that list, I think the models that stand out are the XPS 15, X1 Yoga and Surface Book. I’ve probably been looking most closely at the Yoga, but the XPS deserves some closer attention – especially as the price seems a bit more affordable. The Surface Book looks nice, but for me I think it’s in 3rd place behind the other two.

Let me know of any corrections or suggestions for other models that I should consider and anything I’ve overlooked.

Sunday, 14 February 2016

Book review: Why

As part of their support for user groups, O’Reilly sent me a free copy of “Why: A Guide to Finding and Using Causes ” by Samantha Kleinberg to review.

Kleinberg is an Assistant Professor of Computer Science, so I was interested to see what she had to say about finding “causes”. It probably wouldn’t be the first book I chose if I was browsing, but I’m always interested in learning new things.

What I liked about this book was the use of written examples and illustrations. The first chapter opens with the story of Sally Clark. A tragic miscarriage of justice that resulted in Clark serving 3 years in prison for the murder of her babies. One of the significant pieces of evidence that was used to convict Clark was the suggestion that the probability of two babies dying of SIDS was 1 in 73 million. This is wrong, because the witness (a medical expert) didn’t understand statistics and probability. The expert witness believed Clark was the cause of death the two babies.

The Clark story isn’t the only one told. I’m glad for the generous sprinkling of those examples – without which it would be pretty dry going. It is very helpful to bring things back to something you can relate to.

A warning, this is a pretty in-depth book. I can’t say I found it an easy read, but there’s plenty of detail there.

Before reading this book I guess I assumed that finding the cause for something was a pretty straight forward. Turns out the correct method is “it depends”.

Trying to identify the real cause of an event is not always easy. Kleinberg takes us on a journey to better understand ways (and there are more than one) of finding causes – Beginnings (concepts), Psychology (how do we learn about causes), Correlation (correlation and causation aren’t the same thing), Time, Observation (watching to learn), Computation (automating the process), Experimentation (experiments and research), Explanation (this caused that), Action (making decisions).

The writer comes from the Computer Science field but she writes in a generally accessible (if a little bit academic) way. There are plenty of references (the notes and bibliography take up a not insignificant amount of the book). I noticed a lot of examples were medically-related, so if you work in the medical field, then I think you would get a lot out of it too.

Finally, a suggestion for the title of the sequel – “Just Because” Smile

Thursday, 28 January 2016

Backwards compatible ignoring Roslyn Analyzer warnings

The “Roslyn” Analyzers are a great new feature that shipped in Visual Studio 2015. One nice thing about them, is you can still add them to a project even if the target platform for a project is not .NET 4.6. This makes sense, as the analyzers just run as part of the compiler – they don’t affect the generated code in any way.

This also means you can safely add analyzers to a project and get all the warnings/errors when using Visual Studio 2015, but you can still open the same project in an older version of Visual Studio and the analyzers are just ignored.

Sometimes you want to suppress a specific warning. It turns out there’s two ways to do this:

SuppressMessageAttribute

The first is the same that you would have done to suppress an old FxCop/Code Analysis violation – using the System.Diagnostics.CodeAnalysis.SuppressMessageAttribute attribute.

[SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]

It turns out, the only bit that Roslyn really cares about is the second parameter. As long as it starts with a valid CheckId, then that violation will be suppressed. My observation is that the first parameter (category) doesn’t seem to matter too much.

[SuppressMessageAttribute("StyleCop", "SA1514")]

Pragmas

The new compiler is much more flexible in disabling warnings and errors. You can now use a compiler pragma to disable a particular warning or error code – and the code isn’t just for the C# language, it can be for an analyzer too. eg.

#pragma warning disable SA1514

One advantage to using pragmas is that you can re-enable them if you want to limit the scope of the pragma to just a particular block of code in a single file.

Backwards-compatible pragmas

The only problem with the pragma approach above is if you try and compile the source code with the older non-Roslyn C# compilers. They haven’t ever heard of this ‘SA1514’ that you’re referring to and will generate a compiler error. The workaround is to wrap the pragmas with a conditional block, like this:

#if VS2015 

#pragma warning disable SA1514
#endif

The final part is to define ‘VS2015’. Do this by editing the .csproj file and adding the following block (insert it after the last configuration/platform-specific PropertyGroup)

<PropertyGroup>   
  <DefineConstants Condition="$(VisualStudioVersion) &gt;= 14 ">$(DefineConstants);VS2015</DefineConstants>
</PropertyGroup>

This has the effect of defining a conditional constant only when we’re compiling with Visual Studio 14 (aka 2015) or above. For earlier versions, the constant is undefined and so the pragma is not visible to the compiler.