Thread

  1. Re: pgstattuple: Use streaming read API in pgstatindex functions

    Shinya Kato <shinya11.kato@gmail.com> — 2025-10-16T08:20:27Z

    Hi,
    
    On Wed, Oct 15, 2025 at 10:25 AM Xuneng Zhou <xunengzhou@gmail.com> wrote:
    
    > Hi,
    >
    > Here’s the updated summary report(cold cache, fragmented index), now
    > including results for the streaming I/O + io_uring configuration.
    >
    > [image: image.png]
    >
    
    Thank you for the additional tests. I can see the image on Gmail, but I
    cannot on pgsql-hackers archive [0], so it might be a good idea to attach
    it and not to paste it on the body.
    
    I saw the patch and have a few minor comments.
    
    + p.current_blocknum = 1;
    
    To improve readability, how about using the following, which is consistent
    with nbtree.c [1]?
    p.current_blocknum = BTREE_METAPAGE + 1;
    
    Similarly, for hash index:
    p.current_blocknum = HASH_METAPAGE + 1;
    
    + /* Unlock and release buffer */
      UnlockReleaseBuffer(buf);
    
    I think this comment is redundant since the function name
    UnlockReleaseBuffer is self-explanatory. I suggest omitting it from
    pgstathashindex and removing the existing one from pgstatindex_impl.
    
    
    [0]
    https://www.postgresql.org/message-id/CABPTF7XyEW_3or2yFxBcHhVWAph5NnThLN%3DqS9cNecM1Uy_K%2Bw%40mail.gmail.com
    [1]
    https://github.com/postgres/postgres/blob/41c674d2e31e8304a6edbcb5183d326798ba00f6/src/backend/access/nbtree/nbtree.c#L1261
    
    -- 
    Best regards,
    Shinya Kato
    NTT OSS Center