app.py: adjust steps boundries and default, allow higher concurrency

app.py

@@ -126,7 +126,7 @@ with gr.Blocks(css=css) as demo:
                             sampler = gr.Dropdown(value="DPM++ 2M Karras", show_label=True, label="Sampling Method", choices=prodia_client.list_samplers())
 
                         with gr.Column(scale=1):
-                            steps = gr.Slider(label="Sampling Steps", minimum=1, maximum=30, value=25, step=1)
+                            steps = gr.Slider(label="Sampling Steps", minimum=1, maximum=25, value=20, step=1)
 
                     with gr.Row():
                         with gr.Column(scale=1):
@@ -147,4 +147,4 @@ with gr.Blocks(css=css) as demo:
 
         text_button.click(flip_text, inputs=[prompt, negative_prompt, model, steps, sampler, cfg_scale, width, height, seed], outputs=image_output)
 
-demo.queue(concurrency_count=16, max_size=20, api_open=False).launch(max_threads=64)
+demo.queue(concurrency_count=24, max_size=32, api_open=False).launch(max_threads=128)