I need to copy large number of small files from one S3 bucket to another. I'm using S3-Dist-Cp command provided by AWS.
s3-dist-cp --src=s3://some-bucket/ --dest=s3://another-bucket/ --groupBy=<some-pattern> --targetSize=<size> --deleteOnSuccess
Now, the problem with this command is that it takes forever to copy all small files and merge them.
Note - Source bucket is being written continuously with new files by some other job and I think s3-dist-cp never catches with last file.
Is there any workaround for this solution? destination bucket will be used by Spark job to process these files.
Related
I have a a few directories with about 1000 files each. The size of a directory is about 30G each.
I need to upload these directories to s3 bucket, but each file needs to be in a separate directory.
I'm using AWS SDK for uploading.
What would be the most efficient way to do it?
Copy directories as they are and move files inside s3 bucket to final destinations?
Run separate command for each file?
For 1st I hope aws libraries will better handle parallelism while updating than I can do with 2nd solution.
But 2nd approach saves me time for moving (in fact copying and deleting) objects inside s3.
Regards
Pawel
I have ~200.000 s3 files that I need to partition, and have made an Athena query to produce a target s3 key for each of the original s3 keys. I can clearly create a script out of this, but how to make the process robust/reliable?
I need to partition csv files using info inside each csv so that each file is moved to a new prefix in the same bucket. The files are mapped 1-to-1, but the new prefix depends on the data inside the file
The copy command for each would be something like:
aws s3 cp s3://bucket/top_prefix/file.csv s3://bucket/top_prefix/var1=X/var2=Y/file.csv
And I can make a single big script to copy all through Athena and bit of SQL, but I am concerned about doing this reliably so that I can be sure that all are copied across, and not have the script fail, timeout etc. Should I "just run the script"? From my machine or better to put it in an ec2 1st? These kinds of questions
This is a one-off, as the application code producing the files in s3 will start outputting directly to partitions.
If each file contains data for only one partition, then you can simply move the files as you have shown. This is quite efficient because the content of the files do not need to be processed.
If, however, lines within the files each belong to different partitions, then you can use Amazon Athena to 'select' lines from an input table and output the lines to a destination table that resides in a different path, with partitioning configured. However, Athena does not "move" the files -- it simply reads them and then stores the output. If you were to do this for new data each time, you would need to use an INSERT statement to copy the new data into an existing output table, then delete the input files from S3.
Since it is one-off, and each file belongs in only one partition, I would recommend you simply "run the script". It will go slightly faster from an EC2 instance, but the data is not uploaded/downloaded -- it all stays within S3.
I often create an Excel spreadsheet with a list of input locations and output locations. I create a formula to build the aws s3 cp <input> <output_path> commands, copy them to a text file and execute it as a batch. Works fine!
You mention that the destination depends on the data inside the object, so it would probably work well as a Python script that would loop through each object, 'peek' inside the object to see where it belongs, then issue a copy_object() command to send it to the right destination. (smart-open ยท PyPI is a great library for reading from an S3 object without having to download it first.)
I have a single bucket with a large number of very small text files (betwen 500 bytes to 1.2k). This bucket currently contains over 1.7 Million files and will be ever increasing.
The way that I add data to this bucket is by generating batches of files (in the order 50.000 files) and transfering those files into the bucket.
Now the problem is this. If I transfer the files one by one in a loop it takes an unbareably long amount of time. So if all the files a in a directory origin_directory I would do
aws s3 cp origin_directory/filename_i s3://my_bucket/filename_i
I would do this command 50000 times.
Right now I'm testing this on a set of about 280K files. Doing this would take approximately 68 hours according to my calculations. However I found out that I can sync:
aws s3 sync origin_directory s3://my_bucket/
Now this, works much much faster. (Will take about 5 hours, according to my calculations). However, the sync needs to figure out what to copy (files present in the directory and not present in the bucket). Since the files in the bucket will be ever increasing, I'm thinking that this will take longer and longer as times moves on.
However, since I delete the information after every sync, I know that the sync operation needs to transfer all files in that directory.
So my question is, is there a way to start a "batch copy" similar to the sync, without actually doing the sync?
You can use:
aws s3 cp --recursive origin_directory/ s3://my_bucket/
This is the same as a sync, but it will not check whether the files already exist.
Also, see Use of Exclude and Include Filters to learn how to specify wildcards (eg all *.txt files).
When copying a large number of files using aws s3 sync or aws s3 cp --recursive, the AWS CLI will parallelize the copying, making it much faster. You can also play with the AWS CLI S3 Configuration to potentially optimize it for your typical types of files (eg copy more files simultaneously).
try using https://github.com/mondain/jets3t
it does this same function but works in parallel, so it will complete the job much faster.
We are using an S3 bucket to store a growing number of small JSON files (~1KB each) that contain some build-related data. Part of our pipeline involves copying these files from S3 and putting them into memory to do some operations.
That copy operation is done via S3 cli tool command that looks something like this:
aws s3 cp s3://bucket-path ~/some/local/path/ --recursive --profile dev-profile
The problem is that the number of json files on S3 is getting pretty large since more are being made every day. It's nothing even close to the capacity of the S3 bucket since the files are so small. However, in practical terms, there's no need to copy ALL these JSON files. Realistically the system would be safe just copying the most recent 100 or so. But we do want to keep older ones around for other purposes.
So my question boils down to: is there a clean way to copy a specific number of files from S3 (maybe sorted by most recent)? Is there some kind of pruning policy we can set on an S3 bucket to delete files older than X days or something?
The aws s3 sync command in the AWS CLI sounds perfect for your needs.
It will copy only files that are New or Modified since the last sync. However, it means that the destination will need to retain a copy of the 'old' files so that they are not copied again.
Alternatively, you could write a script (eg in Python) that lists the objects in S3 and then only copies objects added since the last time the copy was run.
You can set the Lifecycle policies to the S3 buckets which will remove them after certain period of time.
To copy only some days old objects you will need to write a script
I have an S3 bucket in Region A structured like this:
ProviderA-1-1
31423423.jpg
ProviderB-1-1
32423432.jpg
The top level folder is a unique image identifier. The filename is the version of the image.
i want to copy the images to a bucket in Region B, structured like this:
ProviderA-1-1.jpg
ProviderB-1-1.jpg
E.g i don't care about the version. I just want the folder name (which is unique) to be the filename.
The reason i'm doing this is to have a flat structure to make use of image services like Imgix / ImageKit. (they provide on the fly image transformation for images, given a flat source origin)
So, my requirements are:
I need to copy lots (millions of images, ~10TB) of images
The destination bucket is in another region
I need to 'flatten' the structure, and change the name of the images to be the name of the folder they are in (folder names isn't fixed)
I've seen a few answers here suggesting the aws cli is the best approach, but not sure how i can achieve 3. with that?
Sounds like i need to loop through the images one by one, changing the name before i copy. If a script is suggested, i'm most comfortable with .NET - so perhaps the AWS .NET SDK?
This is a once off job, where i need to move the images as quickly and cheaply as possible.
Advice please?
Thanks :)
Yes, a script is required because you are moving and renaming the files.
If you're comfortable with .NET, then use that!
The basic program would be:
Create two S3 clients -- one for source bucket (to obtain the listing) and one for the destination bucket (because copy commands are sent to the destination bucket, which pulls the file from the source bucket) because you are using a different region
Use ListObjects() to obtain a list of the source bucket. Note that it will return 1000 files at a time, so use NextMarker to request the subsequent batch.
Loop through each file and use CopyObject() to simultaneously copy and rename the file. Use your own logic to take the folder name and convert it to a filename. Each file will be copied directly between the buckets, without needing to download/upload
Continue, looping through the list of 1000 files and then get the next 1000 files, etc.
The process could be sped up by using multi-threading but the logic gets a bit hard. It might be easier to simply run a few copies of the program at the same time, each handling a different Prefix range (effectively, folder names).
It's a one-off job, so optimization isn't important.
If you are adding more files in future, the best method would be to create an AWS Lambda function that is triggered whenever a new file is created in S3. The Lambda function would then copy the file to the destination, then exit.
Assuming you have no location constraints set up for your buckets, flattening would simply be:
aws s3 cp --recursive s3://source_bucket/foo/ s3://target_bucket/
assumes you have the CLI installed and required credentials setup correctly. Or you can pass them on command line:
aws --profile profile_A2B --region XXX s3 cp --recursive s3://source_bucket/foo/ s3://target_bucket/ --acl yyy
You don't mention any performance requirements. There are many ways of making transfer faster, depends on many factors. Few blind hints I can give are:
See if transfer acceleration can help you.
In general S3 to S3 transfer is faster than S3 to/from non-S3 location.
See if you can create parallel batches by prefix like:
.
for prefix in {a..z}
do
aws s3 cp --recursive s3://source_bucket/foo/${prefix}* s3://target_bucket/ &
done
If this is not a one time transfer and the transfer acceleration isn't cutting it for you, consider:
download from S3 (in region A) to a local HDD residing in region A.
transfer from local HDD in region A to a local HDD in region B using other methods like Aspera or FileCatalyst or whatever else you can find.
upload from local HDD in region B to S3 (in region B).
I have no practical data to share except that Aspera blows things like FTP out of water, it's not even a competition. YMMV.
John already covered the pseudo code. I'll just make one change to it. Write two separate programs, one to fetch the list of filenames and second to copy. It takes a lot of time to list files if you have millions of them.
Once you've listed the file names in a file, say one per line, it would be pretty easy to parallelize given you can split the file (say split -l 1000 file_list splits).
Use xargs -P or gun parallel to run multiple aws s3 cp commands at once. If you're using shell instead of .NET.
Finally don't forget to set the ACL (and other attributes like TTL etc) on target files during the copy. Doing that after the copy will take a long time.