Here is one more AccuRev vs. ClearCase video to share.  And this one is a crowd favorite.

AccuRev vs. ClearCase in ClearCase Multisite Unsynced

Sure, we all know geographically distributed development teams face lots of challenges.  But ClearCase doesn’t provide a simple solution to this problem.  In fact, with ClearCase Multisite Unsynced, teams have trouble syncing up and don’t allow developers to work the the same branches at the same time.

With AccuReplica from AccuRev, all remote teams can work together and on the same code, like one co-located development organization.

Due to positive feedback from our first blog promoting AccuRev vs. ClearCase parody videos (see the post Issues with ClearCase?), and seeing as ClearCase has not addressed the needs of modern software developers in years, it seems only fitting to share a few more.

Rationally Wrapped

While ClearCase users deal with complicated wrappers and scripts during upgrades, AccuRev is easy to use right out of the box, and doesn’t need any wrappers or scripts.

Developers Revolt

Locked out of ClearCase again?

AccuRev will never lock developers out.

Do these issues resonate with you and your development team?  Read more about how AccuRev auto-synchronizes with ClearCase, providing developers the ability to get up and running with AccuRev at no risk!

While the AccuRev blog rarely digresses from its serious and technical nature, an opportunity to inject light and humorous content has arisen.

About 3 years ago, AccuRev released a series of short parody videos based on customer feedback that compared AccuRev and ClearCase, and even today, the amount of views continue to grow.

While one might think the videos are now outdated, being 3 years old, they are still very much applicable today because, well, the same ClearCase issues exist…

Example 1: ClearCase Installation.

Installing Rationally

Of the many differences between AccuRev and Clearcase, the first can be seen during installation. How long does it take ClearCase admins to install ClearCase? Hours? Days?  AccuRev’s smaller server eliminates the issue of multi-day-long installations.

Is this rational?

by Brad Hart

In just about every situation in the last 8 years where I’ve gone into a prospect to talk about replacing ClearCase, I’ve been asked the question about ClearCase’s Dynamic Views and why AccuRev does not have a similar concept. It’s a fair question coming from those who are familiar with ClearCase and I’m posting this blog to help both give some background information on Dynamic Views and answer some of the common issues raised by former users of ClearCase before they made the switch to AccuRev. I used to work at Rational Software in both Support and in the Field and I spent a number of years as a ClearCase consultant before coming to AccuRev in 2001.

At the time Dynamic views were introduced, there was tremendous pain in the market using a local source copy model, especially in enterprise applications. Disk space was extremely expensive, and it was becoming increasingly infeasible to have large enough disks on each developer’s workstation. Networks were also much slower, and the time required to copy entire sets of source code to each developer’s workstation was unrealistic as applications grew in size and complexity. Dynamic views provided the appearance of each developer having a local copy of the source files, but without the time / disk space overhead associated with having real local copies. They also provided just-in-time access to files across a network connection which was transparent to the end user, similar to the way NFS works. Unlike NFS, which you only can access the latest version of files, the dynamic views allow the developer to reconfigure their view of the files to represent any given configuration past or present. Also, unlike a local copy model, reconfiguring what a developer sees does not require any file copying to reflect the changes. This saves time and money and the savings continue to scale the larger the development group gets.

Does it still hold water?
No. Both workstation and network hardware costs have dramatically dropped in recent years, and the performance has increased exponentially. It is very common and reasonable for developers to have near server-class systems on their desktops. In many cases, it is now a much better time savings to have developers work with local copies of their source files. In fact, Rational’s default usage model for developers is to do their development in a local copy source file model, contradicting the presence of Dynamic views. Dynamic views were a time and cost savings breakthrough when it was introduced, but given the changes in development environments in the current time, it is more often than not seen as a hindrance. There is also a much higher administrative burden associated with Dynamic views. Especially if you are working in a mixed environment (SAMBA, TAS, etc… need to be properly configured and maintained). Also, Dynamic views are notoriously unreliable and unusable over remote connections. Another major objection to Dynamic views from the developer perspective is that most developers don’t want “the rug pulled out from under them.” Your files are constantly changing in your view….how are you supposed to develop/build and test like that? Add in the fact that ClearCase does not have atomic transactions, and developers using Dynamic views will constantly have inconsistent sets of code to work on. Bottom line is that even Rational recommends developers use Snapshot views (like AccuRev workspaces) and only use the Dynamic views for integrations. Since AccuRev truly builds in parallel development, you don’t need an integration view/workspace. All your work can be done directly from one workspace.

Five things I’ve heard from developers on why they think dynamic views are important to an effective development environment:

WYSIWYG: The final test of your code changes before check-in is exactly the same thing as testing the release area code directly. No need to “check it out again in a different place just to make sure I checked in everything right.”

AccuRev allows your private work (keeps) and your check-ins (promote) to all occur from the same place (you don’t have to check out to a different place). AccuRev builds in best-practices like private-branching (workspace streams), atomic transactions, and copy-merge. You don’t get that out of the box with ClearCase. AccuRev’s built-in best practices absolutely improve the entire process. You absolutely must merge against the latest code before you promote your changes (for overlapped files). Plus, developers have total control of their workspace bringing in new changes as they are ready. That way if something is broken, they will know whether it is their code, or the latest code from the mainline. With Dynamic views, you will have to go find out for yourself and it is constantly changing. I have heard a lot of the “rug being pulled out from under me” analogies regarding dynamic views.

Zero-latency perfect synchronization with the release area: no time is ever spent checking out all the files in the entire directory just to see the release area. You are always “seeing” the release area. Your code is the release area.

Running updates in AccuRev is trivial and incremental. Performance far exceeds ClearCase’s snapshot views. You don’t need to check out all the files. Updates just bring in the changes.

Instantaneous creation of a new view into the release area: Suppose you want to do a quick mod and test of the release area code. Just create a new view, make the code mod, and do a build. You are good to go. No time spent doing a full checkout of everything just to modify 1 line of code in 1 file.

With AccuRev, you can simply re-parent one of your workspaces, update, check in your changes…done.

Automatic synchronization with the continuous development of code in the release area. Suppose you have a huge pile of code checked out for 3 weeks, and one week into it somebody checked in a change that broke your implementation. Dynamic views force you to reconcile the merge difference the moment the file is checked in, while it is still fresh in everybody’s mind. No trying to recreate the scenario 2 weeks later because you forgot to do a refresh of your sandbox. Your build will immediately fail, and you can confront the guilty party before they go on to work on other stuff. With dynamic views, the team is always in alignment and working on the code together.

Too much thrashing. This might work for a very small team. This would be mayhem for a large group.

Entire directories can be rearranged without worrying about somebody’s checkout becoming unmanageable. Since everyone instantly adopts all the changes that take place in the release area, all the files in a directory can be moved and changed without you even being aware of it. All of your “checked out sandboxes” instantly are updated to work with the new directory structure. This freedom encourages engineers to create a well structured file hierarchy, even making changes during critical bugfix periods in a product development cycle a non-issue. One does not feel the need to keep around old sandboxes “just in case everything breaks.”

Absolutely no problem for AccuRev. AccuRev has true namespace versioning and handles all elements using element ids. You can work on a file and have someone else rename it and it will cause you no problems at all. When you update, the file will be moved to the correct location and your changes will remain in effect.

This post is not meant to discredit the work done by the ClearCase development team, but rather to point out how Dynamic views have all but become obsolete. The VCR changed home entertainment forever…but you’d have to pull my DVR and DVD players from my cold dead fingers while my VCR is nothing but a fond memory collecting dust in the basement.

What are your thoughts?

-Brad

In May of 2005, the company I worked for, Polycom, decided to switch our Software Configuration Management tool from ClearCase to AccuRev. Initially, this decision was not taken well by the developers in my business unit since they had been using Base ClearCase for several years.  However, after seeing how much easier AccuRev was to use and that it did everything that we needed for our development tasks, we became firm believers that AccuRev really is a “Best of breed” Configuration Management tool.

We evaluated a couple of CM tools before settling on AccuRev.  Among the tools we looked at were IBM Rational ClearCase UCM (which I was very familiar with), CVS, and Accurev.  CVS was being used by development teams in both offices and it was determined to be a tool that would not scale well for us.  After evaluating ClearCase UCM and AccuRev, it was decided that AccuRev was the way to go, for several reasons.  One reason Clearcase UCM did not do well was that we could not even get it to work at one of our offices that was using Linux for development (they were using 9 different types of Linux at the time).  AccuRev positively shined during this part of the evaluation by the fact that it was very easy to setup and use in a Linux environment.  Another reason and a huge advantage for AccuRev was the fact that it was very easy to use over a WAN between multiple sites (i.e., Austin TX and Andover, MA) without a mechanism like MultiSite.  The AccuRev servers that the development team in Andover used were located in Austin, TX.  For the 3 years that that I worked with our team using AccuRev, I never had any major issues using it over the network.  A third big reason was that we also did not have to pay for ClearCase MultiSite licenses which meant a big cost savings for the company.  This last reason was major factor in management choosing AccuRev over ClearCase UCM.

After selecting AccuRev as our new CM tool, we had to migrate the current source code that was in ClearCase. At the time that we were doing this, there was no migration tool to take source code in ClearCase and move it over to AccuRev. We decided to archive the existing ClearCase Version Object Bases (VOBs) and leave them as is on their current servers in the Andover, MA office.  This was determined by our management team to be the best way to start off using AccuRev.  Most of this legacy code was for really old products that had been “End of Lifed”.  So, we were not really losing much by doing this.  We then imported the latest code from the VOBs that we cared about.  The import of this source code was just brought in as flat files.   This worked out well for us and for those who wanted to keep legacy history around.

The training for using AccuRev was very short.  AccuRev sent a trainer to our office in Andover and we had 2 groups of developers (about 15 each), attend a training session that was less than 3 hours long.  One half day of training for the developers.  It was that simple.  After this training, I was available to help the user community with any questions that they had.  I do have to say, I did not spend much time at all helping fix issues related to AccuRev.  For any issues that did come up and I couldn’t help out with immediately, AccuRev Technical Support was always there to help.  For the record, I did not attend any special AccuRev Administrators Training.  AccuRev does have AccuRev Certified Engineer Training available and that was something I wanted to take.  Actually, whatever administration was needed for AccuRev took place in the Austin, TX office.  The person who did that did it a part time basis.  This is also much different than ClearCase.  I have been a full time ClearCase Administrator at several companies and that is a full time job.  When I was working with ClearCase, at least 20 and up to 30 percent of my time was spent on administrative tasks related to ClearCase.  So, I was able to devote that extra time to work on other types of things, like the install kits for our products using InstallShield.  We had been considering hiring a consultant to do that work and we ended up saving the money that we would have spent on that.

After the import was done, developers were able to create projects and streams very easily. It did take a little while for everyone to get used to the concept of projects and streams.  I had used ClearCase UCM in the past.  So, I had no problem relating to these concepts.  For the rest of the development team, the concepts of projects and streams was very easy to get used to and made a lot of sense to them.   There was a slight learning curve for the developers with using some of the AccuRev utilities like the Version Tree Browser which looked different than the one that they were used to in ClearCase.  There were some concerns about using the AccuRev Merge Tool.  However, I attributed that to the fact that the developers may not have completely mastered the concept of merging in ClearCase, since to me it appeared to me much easier to merge source code in AccuRev than in ClearCase. The ability of the development team to quickly grasp the concepts of AccuRev saved a lot of time that would have been spent training them.  I literally was able to sit with new people on the development team and within a half hour, they were up and running with AccuRev.

Overall, I think that our use of AccuRev made our source code management much easier.  The ability to use the Graphical User Interface for most of our work was very beneficial to us. It was great to be able to create streams (or even projects) based off of a particular stream and to be able to literally see that being done on the screen, for example.  The snapshot concept also worked well for us.  It was also very easy to find the differences between build snapshots.  This helped us produce metrics for management very quickly.  We also had no issues implementing AccuRev commands into our build scripts which made our job easier.  Before we used AccuRev, we would run the builds and access CVS databases in the Austin office.  The builds had to be run at night because the builds took so long copying the code over the WAN from Austin to Andover.  After switching over to AccuRev, the fact that we could access the the AccuRev repositories in Austin directly over the WAN allowed the builds to complete much quicker than when we were doing them using CVS.  We never figured out why the copy of the CVS code took so long, but I can tell you that after switching to AccuRev, the build performance improved at least 25 to 30 percent. We could even run them during the daytime when needed, which was very beneficial to our development team.

As I mentioned above,  AccuRev Technical Support was very helpful with any questions or concerns that we had and I can never say enough good things about them.  AccuRev Tech Support always answered their phone quickly and followed up with us on anything we worked with them on.  Based on my 3 years of experience of using AccuRev, I would highly recommend it to development teams that are deciding on a Source Code Management tool.