Librenix: Concerns about IBM's LVMS for LinuxJun 16, 2000, 18:44 (6 Talkback[s])
(Other stories by Ray Yeargin)
[ Thanks to Ray Yeargin for this link. ]
"IBM recently announced plans to release a Logical Volume Management System [LVMS] to the Linux community. While this is surely good news, and IBM is shaping up to be a major supporter of free software in general and Linux in particular, I am not convinced that IBM's LVMS will be an important addition to Linux."
"...the second problem is the important one -- and it arises from what may be the most appealing feature of this technology; the ability to resize a filesystem while it's mounted and in use. ... Using this feature, however, creates the following problems. The filesystems themselves become fragmented across a single disk as they are extended. Further, filesystems grow across multiple disks in an unplanned way. These effects result in higher seek times and, therefore, slower access to data even when only a single file is read. Worse, they limit your ability to physically isolate related files from each other so that reading a database index might interfere with reading the very database file the index points to."
"LVMS is a complex piece of software doing a very sensitive job. Those who actually need it will be few and they will require it to be solid and proven. With several competing alternatives pulling away would-be users, the adopters of LVMS will be fewer still. Without a big base of users -- and barring a significant effort on the part of IBM -- will LVMS ever get the extensive development and testing it must have to become properly proven?"