Use higher priority queues for message sending

SignalServiceKit/src/Loki/API/LokiAPI+SwarmAPI.swift

@@ -5,7 +5,6 @@ public extension LokiAPI {
 
     fileprivate static let seedNodePool: Set<String> = [ "https://storage.seed1.loki.network", "https://storage.seed3.loki.network", "https://public.loki.foundation" ]
 
-    /// Only ever modified from `LokiAPI.errorHandlingQueue` to avoid race conditions.
     internal static var snodeFailureCount: [LokiAPITarget:UInt] = [:]
     internal static var snodePool: Set<LokiAPITarget> = []
     internal static var swarmCache: [String:[LokiAPITarget]] = [:] // TODO: Make this set based?

SignalServiceKit/src/Loki/Protocol/Multi Device/MultiDeviceProtocol.swift

@@ -18,8 +18,6 @@ public final class MultiDeviceProtocol : NSObject {
     /// A mapping from hex encoded public key to date updated.
     public static var lastDeviceLinkUpdate: [String:Date] = [:]
 
-    // TODO: I don't think stateQueue actually helps avoid race conditions
-
     internal static var storage: OWSPrimaryStorage { OWSPrimaryStorage.shared() }
 
     // MARK: - Settings
@@ -317,10 +315,10 @@ public extension MultiDeviceProtocol {
         }
         if timeSinceLastUpdate > deviceLinkUpdateInterval {
             let masterHexEncodedPublicKey = storage.getMasterHexEncodedPublicKey(for: hexEncodedPublicKey, in: transaction) ?? hexEncodedPublicKey
-            LokiFileServerAPI.getDeviceLinks(associatedWith: masterHexEncodedPublicKey).done(on: DispatchQueue.global()) { _ in
+            LokiFileServerAPI.getDeviceLinks(associatedWith: masterHexEncodedPublicKey).done2 { _ in
                 getDestinations()
                 lastDeviceLinkUpdate[hexEncodedPublicKey] = Date()
-            }.catch(on: DispatchQueue.global()) { error in
+            }.catch2 { error in
                 if (error as? LokiDotNetAPI.LokiDotNetAPIError) == LokiDotNetAPI.LokiDotNetAPIError.parsingFailed {
                     // Don't immediately re-fetch in case of failure due to a parsing error
                     lastDeviceLinkUpdate[hexEncodedPublicKey] = Date()

SignalServiceKit/src/Loki/Utilities/Promise+Retrying.swift

@@ -1,8 +1,6 @@
 import PromiseKit
 
 /// Retry the promise constructed in `body` up to `maxRetryCount` times.
-///
-/// - Note: Intentionally explicit about the recovery queue at the call site.
 internal func attempt<T>(maxRetryCount: UInt, recoveringOn queue: DispatchQueue = .global(qos: .userInitiated), body: @escaping () -> Promise<T>) -> Promise<T> {
     var retryCount = 0
     func attempt() -> Promise<T> {

SignalServiceKit/src/Messages/OWSMessageSender.m

@@ -373,7 +373,7 @@ NSString *const OWSMessageSenderRateLimitedException = @"RateLimitedException";
         } error:nil];
     }
     
-    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
         NSMutableArray<NSString *> *allAttachmentIds = [NSMutableArray new];
 
         // This method will use a read/write transaction. This transaction

SignalServiceKit/src/Network/MessageSenderJobQueue.swift

@@ -147,6 +147,7 @@ public class MessageSenderJobQueue: NSObject, JobQueue {
             let operationQueue = OperationQueue()
             operationQueue.name = "SendingQueue:\(threadId)"
             operationQueue.maxConcurrentOperationCount = 1
+            operationQueue.qualityOfService = .userInitiated
 
             senderQueues[threadId] = operationQueue
 

SignalServiceKit/src/Util/JobQueue.swift

@@ -126,21 +126,21 @@ public extension JobQueue {
 
         jobRecord.save(with: transaction)
 
-        transaction.addCompletionQueue(.global()) {
+        transaction.addCompletionQueue(DispatchQueue.global(qos: .userInitiated)) {
             self.startWorkWhenAppIsReady()
         }
     }
 
     func startWorkWhenAppIsReady() {
         guard !CurrentAppContext().isRunningTests else {
-            DispatchQueue.global().async {
+            DispatchQueue.global(qos: .userInitiated).async {
                 self.workStep()
             }
             return
         }
 
         AppReadiness.runNowOrWhenAppDidBecomeReady {
-            DispatchQueue.global().async {
+            DispatchQueue.global(qos: .userInitiated).async {
                 self.workStep()
             }
         }
@@ -190,7 +190,7 @@ public extension JobQueue {
                 owsFailDebug("unexpected error")
             }
 
-            DispatchQueue.global().async {
+            DispatchQueue.global(qos: .userInitiated).async {
                 self.workStep()
             }
         }