Re: make -j4 gets stuck w/ ccache over NFS

[Martin Pool <mbp@sourcefrog.net>]

On Mon, 06 Dec 2004 21:24:29 -0500, Mark M. Hoffman wrote:

> Hello:
> 
> I'm using ccache version 2.4 [1].  I just changed ~/.ccache to a symbolic
> link to a directory which is NFS mounted [2].  The kernel source itself is
> on a local FS.  With the ccache suitably primed, when I do a kernel
> compile using 'make -j4' it seems to get stuck for seconds at a time. 
> When it gets unstuck, it blows through a handful of files and then gets
> stuck again.
> 
> When it is stuck, both NFS client and server are almost totally idle.  The
> network itself has almost no other traffic.  It doesn't seem to matter if
> I mount NFS w/ udp or tcp (v3 in both cases).
> 
> If I move ~/.ccache to a local FS, it never gets stuck.  If I just use
> 'make' or even 'make -j2', (I'm pretty sure but not 100%) it never gets
> stuck.

Perhaps ccache is getting jammed/deadlocked trying to take a lock on NFS. 
Maybe you should try getting an ethereal dump of the network traffic.

-- 
Martin