From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 09 Mar 2016 23:21:01 GMT
Subject: Re: [PATCH 04/19] index-helper: new daemon for caching index and related stuff
Message-ID: <xmqqpov3fdb6.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <xmqqtwkffdus.fsf@gitster.mtv.corp.google.com>

Junio C Hamano <gitster@pobox.com> writes:

> David Turner <dturner@twopensource.com> writes:
>
>> From: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
>>
>> Instead of reading the index from disk and worrying about disk
>> corruption, the index is cached in memory (memory bit-flips happen
>> too, but hopefully less often). The result is faster read. Read time
>> is reduced by 70%.
>>
>> The biggest gain is not having to verify the trailing SHA-1, which
>> takes lots of time especially on large index files.

Come to think of it, wouldn't it be far less intrusive change to
just put the index on a ramdisk and skip the trailing SHA-1
verification, to obtain a similar result with the same trade off
(i.e. blindly trusting memory instead of being paranoid)?