Notification: Upcoming scheduled maintenance periods July 7th, 2010 and July 14th, 2010

Skip to first unread message

App Engine Team

Jun 29, 2010, 9:51:36 PM6/29/10
to Google App Engine Downtime Notify
We are scheduling two upcoming maintenance periods:

July 7th, 2010 - 5pm-6pm Pacific Time (July 8th, 0:00 GMT)
July 14th, 2010 - 5pm-6pm Pacific Time (July 15th, 0:00 GMT)

We’d like to point out that, in the week between the two maintenance
periods on July 7th, 2010 and July 14th, 2010, we are expecting that
datastore performance will be impacted and applications will see
higher read/write latencies. This maintenance and the higher latency
in between are an unfortunate, but necessary step in our long-term
plan towards completing the work to address the datastore latency
issues (as described in our recent blog post:
We recognize the inconvenience to applications and their users caused
by this. For this reason, we continue to offer free datastore CPU
usage until we are confident we have cleared these issues.

App Engine Maintenance Behavior

During the hour maintenance periods listed above, the datastore will
be placed into read-only mode and memcache will be disabled. Calls to
the Memcache API will return None or False for write operations, while
read operations will behave as cache misses, returning immediately
without additional latency. It is recommended that critical portions
of your application that depend on the datastore or memcache should
make use of the capabilities API to detect and recover gracefully
during read-only periods. Documentation describing the capabilities
API can be found here:


Note: We are aware of the capabilities API had not been working as
intended during the previous scheduled maintenance period. We have
resolved the issue causing the capabilities API to report incorrect
information during maintenance periods, preventing developers from
implementing graceful degradation. The capabilities API should be
fully functional and function as intended for these upcoming read-only
Reply all
Reply to author
0 new messages