heap-snapshot
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Currently the only Java heap snapshot file formats used commonly are those defined by the hprof profiler. This project is an open attempt at designing a new binary Java heap dump format and perhaps a set of APIs around that form at that could replace the use of the existing hprof binary format.

Goals:

• Size of file should be no larger than the heap size in memory, ideally smaller. e.g. use compression techniques but also allow for the compression to be options.
• Format of file should be extensible so that vendors could add to the file and others can choose to ignore data that doesn't apply to it.
• File format should be platform independent, a file from a Windows version should be able to be processed on any other platform.
• It should be possible to provide transformation code to transform this file to other older formats, like the old hprof binary format or an hprof textual dump, within reason. Similarly, it should be possible to create one of these files from an older hprof binary format file. These transformations would be outside the VM which would ultimately just create this file, on demand.
• Fields should be options, e.g. stack traces (where used), should be allowed to be left out.
• New minor versions of the file should be readable by older processors by simple skipping the new fields. Major releases should be minimized, ideally never happen.
• The format of the file should be documented in detail. We want a more formal specification of the format than has existed in the past with the hprof binary format.
• Java API's and utilities for working with these files are of interest, and some will be developed, but the main intent with this project is the definition of the file format.

The rest and even all of the above can change, but that is the intent right now.

A rough draft 1 proposal will be posted in the next few months, but discussion and even outside proposals will be entertained now.