When I try to load MDN, I get a 503 Service Unavailable or a 504 Gateway Timeout error from Amazon Cloudfront.
It started happening about 15 minutes ago.
If I try to load MDN from a private tab, then the page loads from Cloudfront’s cache.
Update: This seems to have been resolved now.
There were two incidents (my Nov 9 and 10) where the database ran out of connections, and web requests were unable to finish. This did impact all visitors to MDN. I get alerted within a few minutes of requests failing, and manually cleaned up stalled database connections.
There is something we missed in the recent server migration. and we’re still researching what it could be. A MySQL ANALYZE TABLE on Saturday, November 10 seems to have improved the query optimizer, and the issue hasn’t returned. Monday, with the standard traffic, will be a better test if the issue is fixed. We’ll continue monitoring and investigating this week.
I do not get immediate alerts for posts to Discourse, but instead get notified once a day. I suspect this is the same for a lot of staff. For real-time requests, I suggest the #mdn or #mdn-dev channels in IRC (yes, the old ways are still the most used ways).
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