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https://issues.apache.org/jira/browse/CASSANDRA-20190?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17943379#comment-17943379
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Dmitry Konstantinov commented on CASSANDRA-20190:
-------------------------------------------------

https://github.com/apache/cassandra/pull/3936 - I have added a logic to detect 
BE (using a heuristic) on IndexSummary loading with IndexSummary re-creation in 
case of if BE is detected. Test table data with BE offsets summary are added to 
LegacySSTableTest (I do not have a BE machine, so to emulate BE for offsets in 
Summary I commented temporary the following line: offset = 
Integer.reverseBytes(offset);
in 
org.apache.cassandra.io.sstable.indexsummary.IndexSummary.IndexSummarySerializer.serialize


> MemoryUtil.setInt/getInt and similar use the wrong endianness
> -------------------------------------------------------------
>
>                 Key: CASSANDRA-20190
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-20190
>             Project: Apache Cassandra
>          Issue Type: Bug
>          Components: Local/Other
>            Reporter: Branimir Lambov
>            Assignee: Dmitry Konstantinov
>            Priority: Normal
>             Fix For: 5.0.x, 5.x
>
>          Time Spent: 1h 20m
>  Remaining Estimate: 0h
>
> `NativeCell`, `NativeClustering` and `NativeDecoratedKey` use the above 
> methods from `MemoryUtil` to write and read data from native memory. As far 
> as I can see they are meant to write data in big endian. They do not (they 
> always correct to little endian).
> Moreover, they disagree with their `ByByte` versions on big-endian machines 
> (which is only likely an issue on aligned-access architectures (x86 and arm 
> should be fine)).
> The same is true for the methods in `Memory`, used by compression metadata as 
> well as index summaries.
> We need to verify that this does not cause any problems, and to change the 
> methods to behave as expected and document the behaviour by explicitly using 
> `ByteOrder.LITTLE_ENDIAN` for any data that may have been persisted on disk 
> with the wrong endianness.
>  
> The current MemoryUtil behaviour (before the fix):
> ||Native 
> order||MemoryUtil.setX||MemoryUtil.setXByByte||MemoryUtil.getX||MemoryUtil.getXByByte||
> |BE|LE|BE|LE|BE|
> |LE|LE|LE|LE|LE|
> shortly: MemoryUtil.setX/getX is LE, MemoryUtil.setXByByte/getXByByte is 
> Native



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