Alberto García

O Grove (Spain), 1978

One of the founding members of Igalia, Alberto loves computing since he got his first ZX Spectrum in the early nineties.

Latest Updates

Alberto García 08/02/2017

QEMU and the qcow2 metadata checks

When choosing a disk image format for your virtual machine one of the factors to take into considerations is its I/O performance. In this post I’ll talk a bit about the internals of qcow2 and about one of the aspects that can affect its performance...

Alberto García 24/05/2016

I/O bursts with QEMU 2.6

QEMU 2.6 was released a few days ago. One new feature that I have been working on is the new way to configure I/O limits in disk drives to allow bursts and increase the responsiveness of the virtual machine. In this post I’ll try to explain how it...

Alberto García 17/12/2015

Improving disk I/O performance in QEMU 2.5 with the qcow2 L2 cache

QEMU 2.5 has just been released, with a lot of new features. As with the previous release, we have also created a video changelog. I plan to write a few blog posts explaining some of the things I have been working on. In this one I’m going to talk...

Filter

By Type:

Commits

qcow2: Allow 'cache-clean-interval' in Linux only

qcow2: Allow 'cache-clean-interval' in Linux only The cache-clean-interval option of qcow2 only works on Linux. However we allow setting it in other systems regardless of whether it works or not. In those systems this option is not simply a...

Alberto García19/01/2017

qcow2: Make qcow2_cache_table_release() work only in Linux

qcow2: Make qcow2_cache_table_release() work only in Linux We are using QEMU_MADV_DONTNEED to discard the memory of individual L2 cache tables. The problem with this is that those semantics are specific to the Linux madvise() system call. Other...

Alberto García19/01/2017

qcow2: Remove stale FIXME comment

qcow2: Remove stale FIXME comment It was from the time when none of the global functions had a qcow2_ prefix. Signed-off-by: Alberto Garcia Signed-off-by: Kevin Wolf

Alberto García19/01/2017

hmp: Make block_stream set an explicit job ID

hmp: Make block_stream set an explicit job ID A job ID is always required in order to create a block job on a non-root node. The default ID (obtained with bdrv_get_device_name()) is otherwise empty in this scenario and the job cannot be created. The...

Alberto García19/01/2017

qemu-iotests: Test the 'base-node' parameter of 'block-stream'

qemu-iotests: Test the 'base-node' parameter of 'block-stream' The block-stream command has traditionally used the 'base' parameter to indicate the image to copy the data from. This test checks that the 'base-node'...

Alberto García19/01/2017