question about dynahash

From: Xiaoyulei <xiaoyulei(at)huawei(dot)com>
To: "pgsql-general(at)postgresql(dot)org" <pgsql-general(at)postgresql(dot)org>
Cc: yetao <yetao1(at)huawei(dot)com>
Subject: question about dynahash
Date: 2014-07-21 06:38:11
Message-ID: E8870A2F6A4B1045B1C292B77EAB207C5BA2E5F7@SZXEMA501-MBX.china.huawei.com
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Hi,
I have a question about dynahash.c.

PG dynahash search, with the increase in the number of elements inserted, the value of high_maskwill be more greater. The calculation method of bucket is hashvalue & high_mask, hashvalue for the same key, each calculated value is the same, but the value of high_mask is changed. So if I need find an element I insert before,the bucket value is not same with the before one. If hash high_mask has adjustment, how to find the elements before? Mask after the change, the calculated bucket value is not a value before, it should not to be able to find.

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