S3 TransferManger CRT Client OOM on large file upload

[thai-op]

Describe the bug

We upload several big 12GB files to S3, and the JVM will OOM because of these:

S3TransferManager transferManager = S3TransferManager.builder().s3Client(S3AsyncClient
                .crtBuilder().targetThroughputInGbps(20.0).minimumPartSizeInBytes(8 * MB).build())
                .build();
// then upload
UploadDirectoryRequest uploadDirectoryRequest = UploadDirectoryRequest.builder()
                    .bucket(outputBucket).s3Prefix(outputFile)
                    .source(Paths.get(inputFile)).build();

DirectoryUpload upload = transferManager.uploadDirectory(uploadDirectoryRequest);
CompletedDirectoryUpload completedDirectoryUpload = upload.completionFuture().join();

### Expected Behavior

Not OOM on a 6gb container for uploading a 12GB file.

### Current Behavior

OOM

### Reproduction Steps

JVM 21 jre. Use 6gb container, JVM setting about the same, generate from large file then upload.

### Possible Solution

_No response_

### Additional Information/Context

_No response_

### AWS Java SDK version used

2.25.15

### JDK version used

openjdk version "21" 2023-09-19 OpenJDK Runtime Environment (build 21+35-2513) OpenJDK 64-Bit Server VM (build 21+35-2513, mixed mode, sharing)

### Operating System and version

Amazon Linux amd64

[zoewangg]

Can you share the stacktrace?

[thai-op]

Yeah, I'll try. It's almost doesn't happen in my local computer, btw. I think this is because my local network is slow & so the s3 crt client is never fast enough to accumulate enough heap to run into OOM error. However, when I run in EC2 in a VPC where there's fast network with S3, the issue immediately happens.

So maybe that will help you pinpoint the issue a bit more while I'm trying to gather a stacktrace & heapdump in prod.

[thai-op]

@zoewangg It doesn't seem to happen with sdk v2.25.15. False alarm. I think we are good here. Thanks!

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