waynr opened a new issue, #7135:
URL: https://github.com/apache/arrow-rs/issues/7135

   **Is your feature request related to a problem or challenge? Please describe 
what you are trying to do.**
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   In https://github.com/influxdata/influxdb/issues/25911, we are discussing 
ways to can record [`trace` 
spans](https://github.com/influxdata/influxdb3_core/tree/main/trace) that 
distinguish between two key code paths in an implementation of `ObjectStore` 
that either retrieves objects from an object store or from a local in-memory 
cache. The problem we have right now is that our `ObjectStore` implementation 
has no way to receive span info passed in from the calling context.
   
   
   **Describe the solution you'd like**
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   This issue is proposing the following:
   
   * Add a new `Session` trait to the `object_store` crate [similar to what 
exists in the 
`datafusion::catalog`](https://docs.rs/datafusion/latest/datafusion/catalog/trait.Session.html)
 
     * This would have a single method that returns a session config similar to 
`datafusion::prelude::SessionConfig`
       * This session config would have similar `set_extension`, 
`with_extension`, and `get_extension` methods that allow storing and retrieving 
`Arc<dyn Any + Send + Sync + 'static>` instances by type ID
   * Add a new set of methods to the `ObjectStore` trait take `&dyn Session` as 
a parameter
     * eg `fn get_with_session(&self, session: &dyn Session, location: &Path)`
     * these methods could have default impls that delegate to the 
corresponding existing method (eg `get_with_session` would just ignore the 
session parameter and call `get` by default
    
   This would allow me to do some refactoring in 
https://github.com/influxdata/influxdb/ and 
https://github.com/influxdata/influxdb3_core/ that would result in passing a 
`&dyn Session` with a properly-parented child span and a custom 
`*_with_session` defined in [impl ObjectStore for 
MemCachedObjectStore](https://github.com/influxdata/influxdb/blob/8daccb7ee8f82ffae99b25236af9645fd60e448b/influxdb3_cache/src/parquet_cache/mod.rs#L668)
 -- resulting in trace spans properly contextualized in the hierarchy of a 
given query which also differentiate between calls that result in cached vs 
object store parquet file retrieval. 
   
   **Describe alternatives you've considered**
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   I've considered:
   
   * Using simple metrics to capture the high-level (ie not contextualized 
within a trace span hierarchy) difference between object store and cached 
parquet file retrievals.
     * Doesn't help us identify when poor query performance is caused by cache 
misses
   * Setting up `MemcachedObjectStore` with its own root hierarchy of spans
     * Also doesn't help us identify when poor query performance is caused by 
cache misses
   
   **Additional context**
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