[ARROW-15341] [Go] ipc.Reader Record Array leak

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Component/s: Go
• Assignee: Unassigned
• Reporter: Christopher Wolff
• Created: 14/Jan/22 22:21
• Updated: 14/Jan/22 22:25
• Resolved: 14/Jan/22 22:25

Description

ipc.Reader produces records whose columns have a reference count of two. As a result, once the reference count of Records produced by the Reader goes to zero, the column arrays will still have a reference count of one and won't be properly accounted for.

The loading of the columns in the record is driven from this loop:
https://github.com/influxdata/idpe/blob/185d09d8250c456e6b8417fde622f921b8850c06/vendor/github.com/apache/arrow/go/arrow/ipc/file_reader.go#L338

The memory for the array buffers is allocated here:
https://github.com/influxdata/idpe/blob/185d09d8250c456e6b8417fde622f921b8850c06/vendor/github.com/apache/arrow/go/arrow/ipc/file_reader.go#L361

ctx.loadArray ultimately calls array.MakeFromData which returns an array with a reference count already set to one.

Finally, array.NewRecord retains each of its columns:
https://github.com/influxdata/idpe/blob/cd8adab2c1d512f68376064cb7089067d4df567f/vendor/github.com/apache/arrow/go/arrow/array/record.go#L156

it seems like the code in ipc.Reader that constructs the column arrays needs to release them once the Record has ownership.