change the default value of enable_bitmapscan to off

From: "hehaochen(at)hotmail(dot)com" <hehaochen(at)hotmail(dot)com>
To: "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: change the default value of enable_bitmapscan to off
Date: 2023-01-14 14:51:03
Message-ID: OSZP286MB1725E184F8E925D4A10B2687A4C39@OSZP286MB1725.JPNP286.PROD.OUTLOOK.COM
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The default is enable_bitmapscan on. However, TPC-H.query17 get slower running on my NVMe SSD (WD SN850) after switching on the parameter: latency drop from 9secs to 16secs. During a B-tree Index Scan, bitmapscan optimization converts random I/O into sequential. However, many users use SSDs rather than HDDs. But they may not know the trick. Is there a possibility that can change the default value to off?

Thanks!

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