I'm trying to compile and run simulations using tcsh shell in unix. How can i track time when the compilation has started and stopped, and what is the disk usage?
Using time you can track the internal CPU time spent on a process. You also can view what top (or similar tools like ps) displays for your process. Typically the CPU minutes spent on that process are shown. You can also use date before and after the process, maybe with option +%s to show the date as seconds since 1970-01-01T00:00:00Z to allow easy arithmetic with it (difference). Keep in mind that CPU time can be larger (more than one CPU used) or smaller (CPU also working on other tasks) than real time. Using date will always show real time. time will try to show both.
Disk usage, however, is more complex. By design, files are not dedicated to a specific process. You can, however, run df before and after the process and compare the two values. You cannot be sure that the difference was created by the process, but if you do several runs, that might help. Also you can use du to find out how much storage size is used in a particular path. This only works if you happen to know (or have a good guess) where the process stores its results in files. In your case, this might be the best way to go as you talk about a compilation job.
You can also have a look at the /proc/<PID>/fd/ directory to see the currently held open file descriptors of a running process.
I know the sticky bit on directories allows file deletion only by the owner of files contained inside the sticky dir.
But I can also chmod 1777 a File and the ls -l cmd shows that the file indeed has the sticky bit set.
Nothing.
From the docs: https://www.freebsd.org/cgi/man.cgi?query=sticky&sektion=7&apropos=0&manpath=FreeBSD+10.3-RELEASE+and+Ports
A special file mode, called the sticky bit (mode S_ISTXT), is used to
indicate special treatment for directories. It is ignored for regular
files. See chmod(2) or the file for an explanation of file
modes.
Erik Bennett linked the Wikipedia article on the history of the sticky bit - its original purpose was a hint to the kernel to try to keep files hot in swap, for performance. Modern OSs have abandoned this feature though.
When set, it instructed the operating system to retain the text segment of the program in swap space after the process exited. This speeds up subsequent executions by allowing the kernel to make a single operation of moving the program from swap to real memory.
One notable problem with "stickied" programs was replacing the executable (for instance, during patching); to do so required removing the sticky bit from the executable, executing the program and exiting to flush the cache, replacing the binary executable, and then restoring the sticky bit.
Currently, this behavior is only operative in HP-UX and UnixWare. Solaris appears to have abandoned this in 2005. The 4.4-Lite release of BSD retained the old sticky bit behavior, but it has been subsequently dropped from OpenBSD (as of release 3.7) and FreeBSD (as of release 2.2.1). No version of Linux has ever supported this traditional behavior.
As we trying to make more frequent builds (and as our site traffic has increased), we've noticed that during higher traffic, the initial post-build page loads spike to 20 or 30 seconds. Our builds are published by copying DLL's + PDB's to a single server which is sync'd to one other server. That file-copy generally takes a few seconds.
What are some contributing factors to this sort of initial latency spike? Are there any commonly taken steps to avoid this problem? (I can't imagine high-traffic site that perform multiple builds/day, if not multiple builds/hour, tolerate this sort of thing.)
The main cause of this delay is ASP.Net doing compilation on the pages during first load, transforming the aspx markup into code.
You can solve this (and is actually listed as the first advantage on this link) by doing a pre-compile during your build. Of course, the trade off to this is longer build times. More information is here: http://msdn.microsoft.com/en-us/library/bb398860(v=vs.100).aspx
If you're using MSBuild to handle your CI builds by using the AspNetCompiler task in MSBuild: http://msdn.microsoft.com/en-us/library/ms164291.aspx
Another advantage this has (And why I tend to use this even in development builds), is if you integrate this into your build process, and you end up with syntax errors on a page, the build will fail, instead of your users being the first one to catch it.
In response to your comment (my response was getting too long for a comment):
Actually, I wasn't even aware of the batch settings myself until now. It looks like setting batch to false makes sense during development to reduce initial load times there. But, it seems that doing so would make asp.net function in assembly-per-page mode, which can slow things down on larger apps. So, probably the best compromise would be in development environments, set batch to false to speed up development time, then use the web.config transforms to set it back to true for production, and use the pre-compiler during the production build. Then you'll only pay the pre-compilation costs once for both servers, and in a way that's not visible to users.
Is this possible to do?
Conceptually, a solution should apply across a lot of possible configurations, ranging from two vim instances running in separate virtual terminals in panes in a tmux window, to being in separate terminals on separate machines in separate geographical regions, one or both connected over network (in other words, the vims are hosted by two separate shell processes, which they would already be under tmux anyhow).
The case that prompted me to ponder this:
I have two tmux panels both with vim open and I want to use the Vim yank/paste to copy across the files.
But it only works if I've got them both running in the same instance of Vim, so I am forced to either:
use tmux's copy/paste feature to get the content over (which is somewhat tedious and finicky), or
use the terminal (PuTTY, iTerm2)'s copy/paste feature to get the content over (which is similarly tedious but not subject to network latency, however this only works up to a certain size of text payload to copy at which point this method will not work at all due to the terminal not knowing the contents of the not-currently-visible parts of the file), or
lose Vim buffer history/context and possibly shell history/context in reopening the file manually in one of the Vim instances in either a split buffer or tab and then closing the other terminal context (much less tedious than 1 for large payloads but more so with small payloads).
This is a bit of a PITA and could all be avoided if I have the foresight of switching to an appropriate terminal already running vim to open my files but the destiny of workflow and habit rarely match up with that which would have been convenient.
So the question is, does there exist a command or the possibility of a straighforwardly-constructed (shell) script that allows me to join buffers across independently running vim instances? Am having a hard time getting Google to answer that adequately.
In the absence of an adequate answer (or if it is determined with reasonable certainty that Vim does not possess the features to accomplish the transfer of buffers across its instances), a good implementation (bindable to keys) for approach 3 above is acceptable.
Meanwhile I'll go back to customizing my vim config further and forcing myself to use as few instances of vim as possible.
No, Vim can't share a session between multiple instances. This is how it's designed and it doesn't provide any session-sharing facility. Registers, on-the-fly mappings/settings, command history, etc. are local to a Vim session and you can't realistically do anything about that.
But your title is a bit misleading: you wrote "buffer" but it looks like you are only after copying/pasting (which involves "register", not "buffers") from one Vim instance to another. Is that right? If so, why don't you simply get yourself a proper build with clipboard support?
Copying/yanking across instances is as easy as "+y in one and "+p in another.
Obviously, this won't work if your Vim instances are on different systems. In such a situation, "+y in the source Vim and system-provided paste in the destination Vim (possibly with :set paste) is the most common solution.
If you are on a Mac, install MacVim and move the accompanying mvim shell script somewhere in your path. You can use the MacVim executable in your terminal with mvim -v.
If you are on Linux, install the vim-gnome package from your package manager.
If you are on Windows, install the latest "Vim without Cream".
But the whole thing looks like an XY problem to me. Using Vim's built-in :e[dit] command efficiently is probably the best solution to what appears to be your underlying problem: editing many files from many different shells.
Assume that I set up an automatic nightly build. What artifacts of the build should I save?
For example:
Input source code
output binaries
Also, how long should I save them, and where?
Do your answers change if I do Continuous Integration?
You shouldn't save anything for the sake of saving it. you should save it because you need it (i.e., QA uses nightly builds to test). At which point, "how long to save it" becomes however long QA wants them.
i wouldn't "save" source code so much as tag/label it. I don't know what source control you're using, but tagging is trivial (performance & disk space) for any quality source control system. Once your build is tagged, unless you need binaries, there really isn't any benefit to just having them around because you can simply re-compile when necessary from source.
Most CI tools let you tag on each successful build. This can become problematic for some systems as you can easily have 100+ tags a day. For such cases I recommend still running a nightly build and only tagging that.
Here are some artifacts/information that I'm used to keep at each build:
The tag name of the snapshot you are building (tag and do a clean checkout before you build)
The build scripts themselfs or their version number (if you treat them as a separate project with its own version control)
The output of the build script: logs and final product
A snapshot of your environment:
compiler version
build tool version
libraries and dll/libs versions
database version (client & server)
ide version
script interpreter version
OS version
source control version (client and server)
versions of other tools used in the process and everything else that might influence the content of your build products. I usually do this with a script that queries all this information and logs it to a text file that should be stored with the other build artifacts.
Ask yourself this question: "if something destroys entirely my build/development environment what information would I need to create a new one so I can redo my build #6547 and end up with the exact same result I got the first time?"
Your answer is what you should keep at each build and it will be a subset or superset of the things I already mentioned.
You can store everything in your SCM (I'd recommend a separate repository), but in this case your question on how long you should keep the items looses sense. Or you should store it to zipped folders or burn a cd/dvd with the build result and artifacts. Whatever you choose, have a backup copy.
You should store them as long as you might need them. How long, will depend on your development team pace and your release cycle.
And no, I don't think it changes if you do continous integration.
This isn't a direct answer to your question, but don't forget to version control the nightly build setup itself. When the project structure changes, you may have to change the build process, which will break older builds from that point on.
In addition to the binaries as everyone else has mentioned I would recomend setting up a symbol server and a source server and making sure you get the correct information out and into those. It will aid in debugging tremendously.
We save the binaries, stripped and unstripped (so we have the exactly same binary, once with and once without debug symbols). Further we build everything twice, once with debug output enabled and once without (again, stripped and unstripped, so every build result in 4 binaries). The build is stored to a directory according to SVN revision number. That way we can always retain the source from the SVN repository by simply checking out this very revision (that way the source is archived as well).
A surprising one I learned about recently: If you're in an environment that might be audited you'll want to save all the output of your build, the script output, the compiler output, etc.
That's the only way you can verify your compiler settings, build steps, etc.
Also, how long to save them for, and where to save them?
Save them until you know that build won't be going to production, iow as long as you have the compiled bits around.
One logical place to save them is your SCM system. Another option is to use a tool that will automatically save them for you, like AnthillPro and its ilk.
We're doing something close to "embedded" development here, and I can tell you what we save:
the SVN revision number and timestamp, as well as the machine it was built on and by whom (also burned into the build binaries)
a full build log, showing whether it was a full/incremental build, any interesting (STDERR) output the data baking tools produced, a list of files compiled and any compiler warnings (this compresses very well, being text)
the actual binaries (for anywhere from 1-8 build configurations)
files produced as a side effect of linking: a linker command file, address map, and a sort of "manifest" file indicating what was burned into the final binaries (CRC and size for each), as well as the debugging database (.pdb equivalent)
We also mail out the result of running some tools over the "side-effect" files to interested users. We don't actually archive these since we can reproduce them later, but these reports include:
total and delta of filesystem size, broken down by file type and/or directory
total and delta of code section sizes (.text, .data, .rodata, .bss, .sinit, etc)
When we have unit tests or functional tests (e.g. smoke tests) running, those results show up in the build log.
We've not thrown out anything yet -- given, our target builds usually end up at ~16 or 32 MiB per configuration, and they're fairly compressible.
We do keep uncompressed copies of the binaries around for 1 week for ease of access; after that we keep only the lightly compressed version. About once a month we have a script that extracts each .zip that the build process produces and 7-zips a whole month of build outputs together (which takes advantage of only having small differences per build).
An average day might have a dozen or two builds per project... The buildserver wakes up about every 5 minutes to check for relevant differences and builds. A full .7z on a large very active project for one month might be 7-10GiB, but it's certainly affordable.
For the most part, we've been able to diagnose everything this way. Occasionally there's a hiccup on the buildsystem and a file isn't actually a the revision it's supposed to be when a build happens, but there's usually enough evidence of this in the logs. Sometimes we have to dig out a tool that understands the debugging database format and feed it a few addresses to diagnose a crash (we have automatic stackdumps built into the product). But usually all the information needed is there.
We haven't had to crack the .7z archives yet, to mention. But we have the info there, and I have some interesting ideas on how to mine bits of useful data from it.
Save what can't be reproduced easily. I work on FPGAs where only the FPGA team have the tools and some cores (libraries) of the design are licensed to compile on only one machine. So we save the output bitstreams. But try to check them over one another rather than with a date/time/version stamp.
Save as in check in to source code control or just on disk? Save nothing to source code control. All derived files should be visible in the file system and available to developers. Don't checkin binaries, code generated from XML files, message digests etc. A separate packaging step will make these end products available. As you have the change number you can always reproduce the build if necessary assuming of course everything you need to do a build is completely in the tree and is available to all builds by syncing.
I would save your built binaries for exactly as long as they have a chance to go into production or be used by some other team (like a QA group). Once something has left production, what you do with it can vary a lot. For a lot of teams, they'll keep just their most recent prior build around (for rollback) and otherwise discard their builds.
Others have regulatory requirements to keep anything that went into production around for as long as seven years (banks). If you are a product company, I'd keep around any binary a customer might have installed in case a tech support guy wants to install the same version.