To control drops you can use hold-queue or queue-limit
Hold-queue:
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Output drops are caused by a congested interface.
The ultimate solution to resolve the problem is to increase the line speed.
However, there are ways to prevent, decrease, or control output drops
when you do not want to increase the line speed.
You can prevent output drops only if output drops are a consequence of short bursts of data.
If output drops are caused by a constant high-rate flow, you cannot prevent the drops.
However, you can control them.
When packets are processed, they are sent to the output queue of the outgoing interface.
queue-limit:
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The layer-3 queue always has a queue limit. This value defines the number of packets inside the queue.
When this queue fills, the router initiates a drop policy.
This policy can be tail drop or Weighted Random Early Detection (WRED).
In other words, the queue limit defines how many packets can be stored in the layer-3 queue
before drops start to occur.
The router automatically assigns a default queue-limit value.
The calculated value varies with the queueing method and with the platform. Importantly,
the queue limit needs to be small enough to avoid introducing latency due to queueing,
but large enough to avoid drops and a resulting impact to TCP-based flows.
The queue-limit command applies only to classes configured with Class-Based,
Weighted Fair Queuing (CBWFQ) using the bandwidth command.
The default queue-limit value varies with the platform
Note: If you increase the output queue in an attempt to prevent output drops.
If packets stay too long in the output queue, TCP timers can expire and trigger retransmission.
Retransmitted packets only congest the outgoing interface even more.
If output drops still occur after you adjust the configuration of the router as recommended,
it means that you cannot prevent or decrease output drops. However, you can control them,
and this can be as effective as prevention.
I would Suggest to increase the hold-queue and queue-limit in little increments and monitor how its effect the drops.
