Custom Query (1145 matches)

Reported by ghudson, 16 years ago.

Over time, creating and destroying LVM snapshots appears to get progressively slower. The slowdown is very gradual; on debuild the problem is likely to never become noticeable, but on linux-build-10 the presence of autodebathenify is causing a visible issue. Currently it takes about 105 seconds to create and tear down an schroot; it used to only take a few seconds.

Unfortunately, cleaning up leaked snapshots (there were about six as of yesterday) does not help, nor does rebooting. Backups of the LVM metadata were piling up in /etc/lvm/archive, but this was not the problem; nuking that directory and turning off archive snapshots does not help. Presumably there is some state inside the volume group which is piling up; I have not found any tools which will let me analyze the internal data structures at that level or perform any kind of garbage collection on them. "lvscan" is also very slow to complete.

It's conceivable that upgrading the kernel on the build server would help (the machine has not been kept up to date with Ubuntu). Barring that, the only temporary remediation I'm aware of is to blow away and recreate the volume group and re-make all the build chroots, a process which would be risky since I believe make-build-chroot does not work with current debootstrap (a separate issue).

A radical solution would be to use the unionfs schroot patch, as proposed in #97. That would eliminate the issue entirely, perhaps in exchange for other issues.

Reported by jdreed, 12 years ago.

At some point, Dell will likely come out with new hardware. It may or may not work with Natty. We should consider bumping the PXE server stage1 kernel to Precise, pending confirmation of hardware support.

Reported by jdreed, 12 years ago.

The 7010s will have 8GB of RAM, and as of this fall, the 755s will be the only machines remaining with 2GB. We should bump the size of the chroot's ramdisk to reflect this and allow for larger temporary files.