Abstract: An access node of a distributed service collects workload data pertaining to at least one peer group of access nodes established for handling client requests. During a particular load shedding analysis, the access node uses the collected metrics to detect that a triggering condition for load shedding with respect to a set of persistent client connections has been met. Each persistent client connection is set up to be usable for a plurality of client requests. The access node initiates a phased termination of at least one selected persistent client connection. The phased termination comprises allowing completion of in-flight requests on the connection and rejecting new requests on the connection.

Abstract: A low latency metadata subsystem for file systems in low latency (LL) mode in a distributed file storage service (DFSS). An LL server (LLS) may receive metadata requests from an access node of the DFSS. For read operations, the LLS may check a local cache of metadata and, for cache hits, retrieve the metadata from the cache. For cache misses, the metadata may be fetched from the storage subsystem of the DFSS and cached. For write operations, the LLS may write entries into a journal for the file system and notify the access node after the journal entries are committed to the journal; the journal entries are asynchronously committed in the storage subsystem. The access node may communicate with the storage subsystem to perform data reads and writes for the LL file system.

Abstract: A low latency metadata subsystem for file systems in low latency (LL) mode in a distributed file storage service (DFSS). An LL server (LLS) may receive metadata requests from an access node of the DFSS. For read operations, the LLS may check a local cache of metadata and, for cache hits, retrieve the metadata from the cache. For cache misses, the metadata may be fetched from the storage subsystem of the DFSS and cached. For write operations, the LLS may write entries into a journal for the file system and notify the access node after the journal entries are committed to the journal; the journal entries are asynchronously committed in the storage subsystem. The access node may communicate with the storage subsystem to perform data reads and writes for the LL file system.