Returns existing or new queue for user. MaxQueriers is used to compute which queriers should handle requests for this user. If maxQueriers is <= 0, all queriers can handle this user's requests. If maxQueriers has changed since the last call, queriers for this are recomputed. It's also responsible to
(userID string, maxQueriers int)
| 124 | // If maxQueriers has changed since the last call, queriers for this are recomputed. |
| 125 | // It's also responsible to store user configs and update the attributes if related configs have changed. |
| 126 | func (q *queues) getOrAddQueue(userID string, maxQueriers int) userRequestQueue { |
| 127 | // Empty user is not allowed, as that would break our users list ("" is used for free spot). |
| 128 | if userID == "" { |
| 129 | return nil |
| 130 | } |
| 131 | |
| 132 | if maxQueriers < 0 { |
| 133 | maxQueriers = 0 |
| 134 | } |
| 135 | |
| 136 | q.queuesMx.Lock() |
| 137 | defer q.queuesMx.Unlock() |
| 138 | |
| 139 | uq := q.userQueues[userID] |
| 140 | priorityEnabled := q.limits.QueryPriority(userID).Enabled |
| 141 | maxOutstanding := q.limits.MaxOutstandingPerTenant(userID) |
| 142 | priorityList := getPriorityList(q.limits.QueryPriority(userID), maxQueriers) |
| 143 | |
| 144 | if uq == nil { |
| 145 | uq = &userQueue{ |
| 146 | seed: util.ShuffleShardSeed(userID, ""), |
| 147 | index: -1, |
| 148 | } |
| 149 | |
| 150 | uq.queue = q.createUserRequestQueue(userID) |
| 151 | uq.maxOutstanding = q.limits.MaxOutstandingPerTenant(userID) |
| 152 | q.userQueues[userID] = uq |
| 153 | |
| 154 | // Add user to the list of users... find first free spot, and put it there. |
| 155 | for ix, u := range q.users { |
| 156 | if u == "" { |
| 157 | uq.index = ix |
| 158 | q.users[ix] = userID |
| 159 | break |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | // ... or add to the end. |
| 164 | if uq.index < 0 { |
| 165 | uq.index = len(q.users) |
| 166 | q.users = append(q.users, userID) |
| 167 | } |
| 168 | } else if (uq.priorityEnabled != priorityEnabled) || (!priorityEnabled && uq.maxOutstanding != maxOutstanding) { |
| 169 | tmpQueue := q.createUserRequestQueue(userID) |
| 170 | |
| 171 | // flush to new queue |
| 172 | // If the new limit is lower than the current number of requests, |
| 173 | // the excess requests (newest ones) will be dropped to prevent deadlocks. |
| 174 | for (uq.queue.length() > 0) && (tmpQueue.length() < maxOutstanding) { |
| 175 | tmpQueue.enqueueRequest(uq.queue.dequeueRequest(0, false)) |
| 176 | } |
| 177 | |
| 178 | uq.queue = tmpQueue |
| 179 | uq.maxOutstanding = q.limits.MaxOutstandingPerTenant(userID) |
| 180 | uq.priorityEnabled = priorityEnabled |
| 181 | } |
| 182 | |
| 183 | if uq.maxQueriers != maxQueriers { |