+static int
+common_fifo_tuning_callback (session_t * s, svm_fifo_t * f,
+ session_ft_action_t act, u32 bytes)
+{
+ proxy_main_t *pm = &proxy_main;
+
+ segment_manager_t *sm = segment_manager_get (f->segment_manager);
+ fifo_segment_t *fs = segment_manager_get_segment (sm, f->segment_index);
+
+ u8 seg_usage = fifo_segment_get_mem_usage (fs);
+ u32 fifo_in_use = svm_fifo_max_dequeue_prod (f);
+ u32 fifo_size = svm_fifo_size (f);
+ u8 fifo_usage = fifo_in_use * 100 / fifo_size;
+ u8 update_size = 0;
+
+ ASSERT (act < SESSION_FT_ACTION_N_ACTIONS);
+
+ if (act == SESSION_FT_ACTION_ENQUEUED)
+ {
+ if (seg_usage < pm->low_watermark && fifo_usage > 50)
+ update_size = fifo_in_use;
+ else if (seg_usage < pm->high_watermark && fifo_usage > 80)
+ update_size = fifo_in_use;
+
+ update_size = clib_min (update_size, sm->max_fifo_size - fifo_size);
+ if (update_size)
+ svm_fifo_set_size (f, fifo_size + update_size);
+ }
+ else /* dequeued */
+ {
+ if (seg_usage > pm->high_watermark || fifo_usage < 20)
+ update_size = bytes;
+ else if (seg_usage > pm->low_watermark && fifo_usage < 50)
+ update_size = (bytes / 2);
+
+ ASSERT (fifo_size >= 4096);
+ update_size = clib_min (update_size, fifo_size - 4096);
+ if (update_size)
+ svm_fifo_set_size (f, fifo_size - update_size);
+ }
+
+ return 0;
+}
+