From 5308248961d0d2158189b1cc81f027cd755b46ca Mon Sep 17 00:00:00 2001 From: Andrea Mazzoleni Date: Mon, 23 Sep 2013 22:18:41 +0200 Subject: [PATCH] New item for TODO. --- TODO | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/TODO b/TODO index 6e9a76f1..82313cf2 100644 --- a/TODO +++ b/TODO @@ -96,6 +96,13 @@ in the same disk. This is possible if the data in the same disk uses parity addresses not contained in the parity file present in the same disk. +* Use smaller hashes to reduce the memory occupation. We can truncate the 128 bits hash +to 32 or 64 bits and reduce the memory usage by a factor of 4 or 2. +ZFS, and Btrfs supports the 32 bit CRCs. To identify bad blocks it should be enough. +But this likely means to drop the dup and --import feature. We cannot trust a 32 bits hash +as a 128 bits one to search for blocks. +It should be optional, only for architectures with very low memory. + * The data could be compressed before processing, resulting in parity block of fixed size, but matching different data block sizes. The complexity is that a file blocks will have to be allocated at runtime,