diff --git a/services/qbittorrent.nix b/services/qbittorrent.nix
index 4ea5c57..1064651 100644
--- a/services/qbittorrent.nix
+++ b/services/qbittorrent.nix
@@ -54,11 +54,11 @@
     serverConfig.BitTorrent = {
       Session = {
         MaxConnectionsPerTorrent = 100;
-        MaxUploadsPerTorrent = 15;
+        MaxUploadsPerTorrent = 50;
         MaxConnections = -1;
         MaxUploads = -1;
 
-        MaxActiveCheckingTorrents = 2; # reduce disk pressure from concurrent hash checks
+        MaxActiveCheckingTorrents = 2;
 
         # queueing
         QueueingSystemEnabled = true;
@@ -89,7 +89,7 @@
         inherit (config.services.qbittorrent.serverConfig.Preferences.Downloads) TempPath;
         TempPathEnabled = true;
 
-        ConnectionSpeed = 100;
+        ConnectionSpeed = 200; # half-open connections/s; faster peer discovery
 
         SaveResumeDataInterval = 300; # save resume data every 5 min (default 60s)
         ResumeDataStorageType = "SQLite"; # SQLite is more efficient than legacy per-file .fastresume storage
@@ -100,29 +100,20 @@
         DisableAutoTMMTriggers.DefaultSavePathChanged = false;
 
         ChokingAlgorithm = "RateBased";
+        SeedChokingAlgorithm = "FastestUpload"; # unchoke peers we upload to fastest
         PieceExtentAffinity = true;
         SuggestMode = true;
 
-        # max_queued_disk_bytes: the max bytes waiting in the disk I/O queue.
-        # When this limit is reached, peer connections stop reading from their
-        # sockets until the disk thread catches up -- causing the spike-then-zero
-        # pattern. Default is 1MB; high_performance_seed() uses 7MB.
-        # 64MB is above the preset but justified for slow raidz1 HDD random writes
-        # where ZFS txg commits cause periodic I/O stalls.
-        DiskQueueSize = 67108864; # 64MB
-
         # POSIX-compliant disk I/O: uses pread/pwrite instead of mmap.
         # On ZFS, mmap forces data into BOTH ARC and Linux page cache (double-caching),
         # wasting RAM. pread/pwrite goes only through ARC, maximizing its effectiveness.
-        # Saved 26 gb of memory!!
         DiskIOType = "Posix";
 
-        # === Network buffer tuning (from libtorrent high_performance_seed preset) ===
-        # "always stuff at least 1 MiB down each peer pipe, to quickly ramp up send rates"
-        SendBufferLowWatermark = 1024; # 1MB (KiB) -- matches high_performance_seed
-        # "of 500 ms, and a send rate of 4 MB/s, the upper limit should be 2 MB"
-        SendBufferWatermark = 3072; # 3MB (KiB) -- matches high_performance_seed
-        # "put 1.5 seconds worth of data in the send buffer"
+        FilePoolSize = 500; # keep more files open to reduce open/close overhead
+        AioThreads = 24; # 6 cores * 4; better disk I/O parallelism
+
+        SendBufferLowWatermark = 512; # 512 KiB -- trigger reads sooner to prevent upload stalls
+        SendBufferWatermark = 3072; # 3 MiB -- matches high_performance_seed
         SendBufferWatermarkFactor = 150; # percent -- matches high_performance_seed
       };