I am beginning to study the use of virtual machines with realtime applications, specifically network applications.
While I do understand the limitations and concerns, I'd like to get ideas as to how to get started on this task.
I am going to use a DPDK sample application over Linux, and probably use VMWare for starters. However, I do not know what my first steps with respect to setting up VMWare should be.
First I think it is better to use open source solution like QUEM/KVM for your virtualization platform. Many platform exist for run high performance network functions on virtualized platforms you can see OpenNetVM for example in order to get basic ideas.
I'm having a little trouble trying to make an HTTP connection on my Blackberry Torch 9800. Here is the line where the problem occurs:
HttpConnection connection = (HttpConnection)Connector.open(URL);
My phone has no data plan and I was trying to do this through wifi. I've been doing it fine this way for a few months now. But suddenly it's giving me a CriticalIOException.
Here is my connection string:
http://mysite.mycompany.com/mws/MyWebService/MyWebService.asmx;interface=wifi
I don't know why this is happening and I don't know what to do about it. Any help would be greatly appreciated.
Thanks!
Please, please don't keep using that legacy Connector.open() approach. This was the way connections were opened in JavaME, and since RIM built its libraries on top of them, they came up with a suffix-based hack to select the transport type. this caused dirty code prone to break, and caused so much pain to new developers (and also senior ones).
RIM introduced ConnectionFactory in OS 5.0 specifically to solve this kind of problems. This was back in 2008, guys we're in 2012!
Have a look at it.
Typically when using the wifi appender, the deviceside appender is used as well. I'm not sure if this is related to your problem, though.
;deviceside=true;interface=wifi
Using Cimplicity Plant Edition we noticed that some projects seem to take an eternity loading. In particular the process seems to hang during the "ROUTING" phase.
Finally found a setting that really helped speed this up. If you have multiple network interfaces, it appears that Cimplicity takes longer to get through the ROUTING phase. To help it favor the network interface to your devices, go into the Advanced TCP/IP settings for each one and change the "Interface metric" numbers.
This link describes what the Interface Metric settings are for: http://www.windowsreference.com/windows-2000/change-the-interface-metric-on-a-network-adapter/
but simply setting these differently on each interface sped things up a lot for us. Hope that helps anyone else out there who is frustrated.
Does anyone have any idea about any songCatcher library for Linux? songCatcher is based on the acoustic fingerprints.
I managed to find one "Audio-Ofa-Util-0.04" but I'm facing problem in using it. Or if someone can help me understand its usage.
Like: > how can I pass an audio file to this tool.
Any specific command for its usage etc.
Any help would be highly appreciated.
Thanks,
Bobby
You might want to check out these other posts on SO:
Is there a free database or web service api for music information (albums, artists, tracks)?
Musicbrainz fingerprinting
The ubuntu package contains an example program using PUIDs* to identify songs in WAVE or MP3 format.
[*] http://wiki.musicbrainz.org/How_PUIDs_Work
I am curious as to what others are using in this situation. I know a couple of the options that are out there like a memcached port or ScaleOutSoftware. The memcached ports don't seem to be actively worked on (correct me if I'm wrong). ScaleOutSoftware is too expensive for me (I don't doubt it is worth it). This is not to say that I don't want to hear about people using memcached or ScaleOutSoftware. I'm just stating what I "know" at this point.
So my question is basically this: for those of you ACTIVELY using distributed caching, what are you using, are you happy with it, and what should I look out for?
I am moving to two servers very soon...both will be at the same location. I use caching fairly heavily (but carefully) to reduce the load on my database server.
Edit: I downloaded Scaleout Software's solution. I've coded for it and it seems to work real well. I just have to decide if my wallet will part with the cash for it. :) Anyone have experiences good or bad with ScaleoutSoftware?
Edit Again: It's been a little while since I asked this? Any more thoughts on it? We ended up buying the solution from ScaleOutSoftware and have been happy with it, but I'm curious what others are doing.
Microsoft has a product pending code-named Velocity. It's still in CTP, and is moving slowly, but looks like it will be pretty good. We'll be beating it up in the near future to see how it handles what we want it to do (> 2 million read/writes per hour). Will post back with results.
There is a 100% native .NET, well documented open source (LGPL) project called Shared Cache. Looks like it is not yet mentioned on SO, but it's promising and should be able to do what most people expect from a distributed cache. It even supports different strategies like distributed or replicated caching etc.
I will update this post with more details as soon as I had a chance to try it on a real project.
We're currently using an incredibly simple cache that I wrote in a couple of hours, based on re-hosting the ASP.NET cache in a Windows Service (more info and source code here). I won't pretend it's anywhere near as optimised as something like Memcached but we were just looking for something simple and free until Velocity came along, and it's held up extremely well even under fairly heavy load.
It comes down to our personal preference for core components - i.e. ones that affect whether the site is available or not - that they are either (a) supported by a vendor with a history of rapid and high quality support, or (b) written by us so that if something goes wrong we can fix it quickly. Open source is all well and good, and indeed we do use some OSS, but if your site is offline then unfortunately newsgroups et al don't have a 1 hour SLA, and just because it's OSS doesn't mean you have the necessary understanding or ability to fix it yourself.
We are using the memcached port for Windows and we are very pleased with it. The enyim.com memcached client API is great and easy to work with. It's also open source, which is a big advantage, if you ask me.
We are now using this setup in a production web-app and it has helped a lot in improving its performance.
There's a great .NET wrapper/port found here on Codeplex. Awesomesauce!
We use memcached with the enyim library in a production environment (www.funda.nl). Works fine, very pleased with it, but we did notice a substantial raise in CPU use on the clients. Presumably due to the serializing/deserializing going on. We do around 1000 reads per second.
One tried and tested product by 100's of customers worldwide is NCache. Its
a feature rich product that lets you store session state in a redundant and highly available manner, lets you share data
within the enterprise as well as bridging for WAN communication essentially acting as a data fabric and lastly it lets you build an elastic caching tier so that when
your application scales, you can add servers to the cache and actually boost performance further.