[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-block] RFC chaning zlib windowBits for QCOW2
From: |
Peter Lieven |
Subject: |
[Qemu-block] RFC chaning zlib windowBits for QCOW2 |
Date: |
Mon, 13 Jul 2015 12:15:43 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 |
Hi,
I was experimenting a little with optimized zlib versions (like zlib-ng) to
optimize the speed of compressed qcow2 generation.
I found out that chaning the windowBits from -12 to -15 alone increases
compression speed by about 15% while lowering
the compressed size by about 6%. As a test case I used a Debian 8.1 disk image.
What is your opinion in chaning the windowBits? The cost is a higher memory usage.
The usage changes from 272k -> 384k for
compression and from 4k -> 32k for decompression.
Peter
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- [Qemu-block] RFC chaning zlib windowBits for QCOW2,
Peter Lieven <=