title: We are dealing with a very serious bug in Parse.com database that has severe implications to our application
body: <p>We are dealing with a very serious bug using Parse.com database that has severe implications to our application.</p>
  
  <p>For a week now, we have seen intermittent operation that degrades our uptime down to less than 20% over the last 2 days.</p>
  
  <p>Using the web query performance and analysis tools, we were able to distill the issue into a clear symptom which seems to anchor in the _User table - a symptom that happens when the system is down. We cannot get to the root cause or a way to get around the issue:</p>
  
  <p>Description:</p>
  
  <p>When the system is down, all queries to _User that try to retrieve a set of users (“containedIn”) where the set has more than 1 user take 30+ seconds and time out. If the same query is sent with a single user ID (“equalTo” or “containedIn” with a single member array) the same query with same conditions returns with a user record immediately.</p>
  
  <p>The same effect happens when we try to retrieve user records as included keys in other object queries (i.e includeKey:@“user”) - if we run that query without including the user or retrieve a single record the query returns successfully immediately. Including the user with more than one response takes 30+ seconds and times out. Even when we limit the query to 1 using query.limit=1, but the containedIn array includes more than 1 ObjectID, the query times out.</p>
  
  <p>It is important to note that :
  1) Our _User count is at 180,000+ at this point, but other collections have MM of records and do not show any such behaviour, and
  2) if the “containedIn:” condition is applied to a different field (such as username) the query DOES NOT time out
  3) we are currently hovering around the 20GB file storage going up and down around that range all week. We have not seen a jump to 40GB as the FAQ states, just a 98%-106% utilisation of the 20GB storage…maybe that is a potential root cause, but we just don’t know.</p>
  
  <p>It feels as though something is “deadlocked” on the objectId index of the _User table… or that the index is corrupted and is being constantly “fixed” locking out queries.</p>
  
  <p>We do not have any visibility as to why the queries take long, why do they fail, or how to approach a solution. We need someone at Parse to work with us to resolve this, as we are losing users for a week - who feel as though our app is just not working…</p>
  
  <p>WE ARE TRYING TO REACH OUT TO SOME HUMAN SUPPORT FROM PARSE FOR A WEEK WITHOUT ANY ANSWER!!!</p>
  
  <p>PLEASE HELP</p>