I am using XAMPP and PHPMyAdmin and I'm trying to load English Wikipedia. Since the file is so big (1.7GB), it take a lot of time. I'm wondering if there is any way to resume the loading process. I have no problem with TimeOut or something like that. The problem is that if my firefox crashes for any reason, the process must start from the scratch.
The part which says allow interrupt is already checked with a check mark. But the problem is that for such a big file that I am loading, it's really difficult to expect to be done without any interrupt. If the laptop is shut down or restarted or so, the process is repeated from the beginning. Is there any way to solve this problem?
In the meantime, I am using
$cfg['UploadDir'] = 'upload';
and load the file from the upload directory on my computer.
Thanks in advance
First, I would recommend against using phpMyAdmin for such a large file. You're going to be constrained by PHP/Apache resource limits for things such as execution time and memory used (or, apparently, some Firefox resource on the client side), to a degree that even if it works properly will have to be done in so many small chunks that it's just not ideal. Even using the UploadDir functionality, you're going to be limited in ways that make it non-ideal to import your file this way. I suggest using the command-line tool for importing a file of this size.
Secondly, if you're going to use phpMyAdmin anyway, it's better to uncompress the file and deal with the raw .sql. This is not intuitive, because of course you think the smaller filesize is better, but phpMyAdmin has to first uncompress the compressed file before it can begin working with it, which can cause problems such as the resource limits (or even running out of disk space). phpMyAdmin can pick up an aborted import, but if you're spending 95% of the execution time uncompressing the file each time, you're going to make very, very slow progress. Actually, I wonder if you're even getting the full file uncompressed on execution before PHP kills the process due to timeout.
phpMyAdmin can pick up execution part way through; you can select which line to begin the import from. If you restart your computer part way through the export, you can use this means to resume your partial import.
my app saves a 1MB file and then another app reads it back. After that I want to sercure delete it. I thought about a ram drive because I know that even with a secure delete appl. something would remain on HDD or SSD. I can accept to lose the content of that file on shutdown. The fact is that I read about some bugs in some ram disk applications bug lists(ex.: imdisk) related to file corruption. Solved bugs but I'm wondering if ram disk apps are secure from file integrity point of view. On the other hand neither a normal disk is 100% secure. My temp file is absolutely important for me. I also protect my file through a sha1 or similar, but let's suppose for a moment that there is no protection, just to understand what is the best solution.
Thanks
Pupillo
What storage place is best certainly depends on the hardware involved, amongst others their age, their MTTF and any previous failures encountered.
I don't think it is possible to give a general answer.
Sounds to me like you are looking for an IPC mechanism, like shared memory.
This would also avoid using file systems and their -- imo very rare -- bugs.
If you think about file corruptions you should also think what will happen on crashes of the involved applications.
So you might have multiple problems:
IPC
Persistency on crashes
Security concerncs, e.g. others reading the involved sections of RAM/HD
I am using Pentaho for reading a very large file. 11GB.
The process is sometime crashing with out of memory exception, and sometimes it will just say process killed.
I am running the job on a machine with 12GB, and giving the process 8 GB.
Is there a way to run the Text File Input step with some configuration to use less memory? maybe use the disk more?
Thanks!
Open up spoon.sh/bat or pan/kettle .sh or .bat and change the -Xmx figure. Search for JAVAMAXMEM Even though you have spare memory unless java is allowed to use it it wont work. although to be fair in your example above i can't really see why/how it would be consuming much memory anyway!
I need to read and process a text file. My processing would be easier if I could use the File.ReadAllLines method but I'm not sure what is the maximum size of the file that could be read with this method without reading by chunks.
I understand that the file size depends on the computer memory. But are still there any recommendations for an average machine?
On a 32-bit operating system, you'll get at most a contiguous chunk of memory around 550 Megabytes, allowing loading a file of half that size. That goes down hill quickly after your program has been running for a while and the virtual memory address space gets fragmented. 100 Megabytes is about all you can hope for.
This is not an issue on a 64-bit operating system.
Since reading a text file one line at a time is just as fast as reading all lines, this should never be a real problem.
I've done stuff like this with 1-2GB before, albeit in Python. I do not think .NET would have a problem, though. But I would only do this for one-off processing.
If you are doing this on a regular basis, you might want to go through the file line by line.
Its bad design unless you know the files sizes vs the computer memory that would be avaiable in the running app.
A better solution would be consider memory mapped files. They use themselvses as page fil storage,
I've got a machine I'm going to be using for development, and it has two 7200 RPM 160 GB SATA HDs in it.
The information I've found on the net so far seems to be a bit conflicted about which things (OS, Swap files, Programs, Solution/Source code/Other data) I should be installing on how many partitions on which drives to get the most benefit from this situation.
Some people suggest having a separate partition for the OS and/or Swap, some don't bother. Some people say the programs should be on the same physical drive as the OS with the data on the other, some the other way around. Same with the Swap and the OS.
I'm going to be installing Vista 64 bit as my OS and regularly using Visual Studio 2008, VMWare Workstation, SQL Server management studio, etc (pretty standard dev tools).
So I'm asking you--how would you do it?
If the drives support RAID configurations in your BIOS, you should do one of the following:
RAID 1 (Mirror) - Since this is a dev machine this will give you the fault tolerance and peace of mind that your code is safe (and the environment since they are such a pain to put together). You get better performance on reads because it can read from both/either drive. You don't get any performance boost on writes though.
RAID 0 - No fault tolerance here, but this is the fastest configuration because you read and write off both drives. Great if you just want as fast as possible performance and you know your code is safe elsewhere (source control) anyway.
Don't worry about mutiple partitions or OS/Data configs because on a dev machine you sort of need it all anyway and you shouldn't be running heavy multi-user databases or anything anyway (like a server).
If your BIOS doesn't support RAID configurations, however, then you might consider doing the OS/Data split over the two drives just to balance out their use (but as you mentioned, keep the programs on the system drive because it will help with caching). Up to you where to put the swap file (OS will give you dump files, but the data drive is probably less utilized).
If they're both going through the same disk controller, there's not going to be much difference performance-wise no matter which way you do it; if you're going to be doing lots of VM's, I would split one drive for OS and swap / Programs and Data, then keep all the VM's on the other drive.
Having all the VM's on an independant drive would let you move that drive to another machine seamlessly if the host fails, or if you upgrade.
Mark one drive as being your warehouse, put all of your source code, data, assets, etc. on there and back it up regularly. You'll want this to be stable and easy to recover. You can even switch My Documents to live here if wanted.
The other drive should contain the OS, drivers, and all applications. This makes it easy and secure to wipe the drive and reinstall the OS every 18-24 months as you tend to have to do with Windows.
If you want to improve performance, some say put the swap on the warehouse drive. This will increase OS performance, but will decrease the life of the drive.
In reality it all depends on your goals. If you need more performance then you even out the activity level. If you need more security then you use RAID and mirror it. My mix provides for easy maintenance with a reasonable level of data security and minimal bit rot problems.
Your most active files will be the registry, page file, and running applications. If you're doing lots of data crunching then those files will be very active as well.
I would suggest if 160gb total capacity will cover your needs (plenty of space for OS, Applications and source code, just depends on what else you plan to put on it), then you should mirror the drives in a RAID 1 unless you will have a server that data is backed up to, an external hard drive, an online backup solution, or some other means of keeping a copy of data on more then one physical drive.
If you need to use all of the drive capacity, I would suggest using the first drive for OS and Applications and second drive for data. Purely for the fact of, if you change computers at some point, the OS on the first drive doesn't do you much good and most Applications would have to be reinstalled, but you could take the entire data drive with you.
As for dividing off the OS, a big downfall of this is not giving the partition enough space and eventually you may need to use partitioning software to steal some space from the other partition on the drive. It never seems to fail that you allocate a certain amount of space for the OS partition, right after install you have several gigs free space so you think you are fine, but as time goes by, things build up on that partition and you run out of space.
With that in mind, I still typically do use an OS partition as it is useful when reloading a system, you can format that partition blowing away the OS but keep the rest of your data. Ways to keep the space build up from happening too fast is change the location of your my documents folder, change environment variables for items such as temp and tmp. However, there are some things that just refuse to put their data anywhere besides on the system partition. I used to use 10gb, these days I go for 20gb.
Dividing your swap space can be useful for keeping drive fragmentation down when letting your swap file grow and shrink as needed. Again this is an issue though of guessing how much swap you need. This will depend a lot on the amount of memory you have and how much stuff you will be running at one time.
For the posters suggesting RAID - it's probably OK at 160GB, but I'd hesitate for anything larger. Soft errors in the drives reduce the overall reliability of the RAID. See these articles for the details:
http://alumnit.ca/~apenwarr/log/?m=200809#08
http://permabit.wordpress.com/2008/08/20/are-fibre-channel-and-scsi-drives-more-reliable/
You can't believe everything you read on the internet, but the reasoning makes sense to me.
Sorry I wasn't actually able to answer your question.
I usually run a box with two drives. One for the OS, swap, typical programs and applications, and one for VMs, "big" apps (e.g., Adobe CS suite, anything that hits the disk a lot on startup, basically).
But I also run a cheap fileserver (just an old machine with a coupla hundred gigs of disk space in RAID1), that I use to store anything related to my various projects. I find this is a much nicer solution than storing everything on my main dev box, doesn't cost much, gives me somewhere to run a webserver, my personal version control, etc.
Although I admit, it really isn't doing much I couldn't do on my machine. I find it's a nice solution as it helps prevent me from spreading stuff around my workstation's filesystem at random by forcing me to keep all my work in one place where it can be easily backed up, copied elsewhere, etc. I can leave it on all night without huge power bills (it uses <50W under load) so it can back itself up to a remote site with a little script, I can connect to it from outside via SSH (so I can always SCP anything I need).
But really the most important benefit is that I store nothing of any value on my workstation box (at least nothing that isn't also on the server). That means if it breaks, or if I want to use my laptop, etc. everything is always accessible.
I would put the OS and all the applications on the first disk (1 partition). Then, put the data from the SQL server (and any other overflow data) on the second disk (1 partition). This is how I'd set up a machine without any other details about what you're building. Also make sure you have a backup so you don't lose work. It might even be worth it to mirror the two drives (if you have RAID capability) so you don't lose any progress if/when one of them fails. Also, backup to an external disk daily. The RAID won't save you when you accidentally delete the wrong thing.
In general I'd try to split up things that are going to be doing a lot of I/O (such as if you have autosave on VS going off fairly frequently) Think of it as sort of I/O multithreading
I've observed significant speedups by putting my virtual machines on a separate disk. Whenever Windows is doing something stupid in the VM (e.g., indexing yet again), it doesn't thrash my Mac's disk quite so badly.
Another issue is that many tools (Visual Studio comes to mind) break in frustrating ways when bits of them are on the non-primary disk.
Use your second disk for big random things.