RocksDB optimizations

tests/resources/scripts/imap_import.py

@@ -0,0 +1,48 @@
+import imaplib
+import socket
+import time
+import threading
+from email.message import Message
+
+def append_message(thread_id, start, end):
+    conn = imaplib.IMAP4('localhost')
+    conn.login('john', '12345')
+    conn.socket().setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+    start_time = time.time()
+
+    for n in range(start, end):
+        msg = Message()
+        msg['From'] = 'somebody@some.where'
+        msg['To'] = 'john@example.org'
+        msg['Message-Id'] = f'unique.message.id.{n}@nowhere'
+        msg['Subject'] = f"This is message #{n}"
+        msg.set_payload('...nothing...')
+
+        response_code, response_details = conn.append('INBOX', '', None, str(msg).encode('utf-8'))
+        if response_code != 'OK':
+            print(f'Thread {thread_id}: Error while appending message #{n}: {response_code} {response_details}')
+            break
+        if n != 0 and n % 100 == 0:
+          elapsed_time = (time.time() - start_time) * 1000 
+          print(f'Thread {thread_id}: Inserting batch {n} took {elapsed_time} ms.', flush=True)
+          start_time = time.time()
+
+    conn.logout()
+
+num_threads = 5
+num_messages = 10000
+messages_per_thread = num_messages // num_threads
+
+threads = []
+for i in range(num_threads):
+    start = i * messages_per_thread
+    end = start + messages_per_thread
+    thread = threading.Thread(target=append_message, args=(i, start, end))
+    threads.append(thread)
+    thread.start()
+
+for thread in threads:
+    thread.join()
+
+print("All messages appended.")
+