Am 16.06.2011 16:43, schrieb Kevin Wolf: > Am 16.06.2011 16:28, schrieb Christoph Hellwig: >> On Wed, Jun 15, 2011 at 09:46:10AM -0400, Federico Simoncelli wrote: >>> qemu-img currently writes disk images using writeback and filling >>> up the cache buffers which are then flushed by the kernel preventing >>> other processes from accessing the storage. >>> This is particularly bad in cluster environments where time-based >>> algorithms might be in place and accessing the storage within >>> certain timeouts is critical. >>> This patch adds the option to choose a cache method when writing >>> disk images. >> >> Allowing to chose the mode is of course fine, but what about also >> choosing a good default? writethrough doesn't really make any sense >> for qemu-img, given that we can trivially flush the cache at the end >> of the operations. I'd also say that using the buffer cache doesn't >> make sense either, as there is little point in caching these operations. > > Right, we need to keep the defaults as they are. That is, for convert > unsafe and for everything else writeback. The patch seems to make > writeback the default for everything. Federico, are you going to fix this in a v4? Kevin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
