Customers using the main U.S. server were affected by server instability on Tuesday and Wednesday of last week brought on by high load. Wednesday's downtime severely impacted our customers' ability to chat with patrons during peak use hours. We understand that you rely on us to provide stable services so you in turn can provide a high quality of virtual reference for your patrons. We sincerely apologize for the disruption during this hectic time of year and thank everyone for their kind patience while we worked to correct the issue. Last Wednesday night, we released an infrastructure upgrade to our main U.S. server designed to greatly enhance our long-term stability, performance, and ability to scale quickly in advance of future crises.
The infrastructure changes are part of a long-term plan to improve performance and fault-tolerance by way of redundant systems distributed across the network. Because the migration to the new architecture was already in-progress, we were able to complete the restructuring by the end of the day on Wednesday and get chat back on track as quickly as possible. Additional servers were added Friday morning to enhance performance.
We take great pride that our server uptime over the last year is 99.91% (including the downtime last week) which is above the industry average of 99%. These changes will ensure our continued high availability moving forward so that you are able to provide the best quality of service for your patrons.