<<On Sun, 12 Sep 1999 23:19:13 -0400 (EDT), Bosko Milekic <[EMAIL PROTECTED]> said:
> This message is in MIME format. The first part should be readable text,
> while the remaining parts are likely unreadable without MIME-aware tools.
> Send mail to [EMAIL PROTECTED] for more info.
It would be preferable if text were sent as text, since MIME-encoded
patches require more effort to read.
> I'm also aware of the possiblity of some people not liking the
> fact that we tsleep() forever (e.g. tsleep(x,x,x,0)).
I don't have any problem with sleeping forever -- but I am concerned
about the possibility of deadlock, especially when client-NFS is
involved. If the problem just moves around and has harder-to-recover
symptoms, the change isn't helping.
The 4.3BSD code had two different behaviors:
- For clusters, if M_WAIT was specified and there was no space
left in mb_map, it panicked. However, m_clalloc was never called with
M_WAIT, so that panic was effectively dead code.
- For mbufs, if M_WAIT was specified and there were no mbufs
available, it would sleep at PZERO - 1 (which was interruptible).
In 4.3, the code was able to deal with cluster allocation failing. We
have a somewhat different situation now, because many network
interface devices have less-flexible DMA mechanisms which don't allow
packet reception into non-contiguous buffers, so we need to have at
least a certain number of clusters available for this purpose.
-GAWollman
--
Garrett A. Wollman | O Siem / We are all family / O Siem / We're all the same
[EMAIL PROTECTED] | O Siem / The fires of freedom
Opinions not those of| Dance in the burning flame
MIT, LCS, CRS, or NSA| - Susan Aglukark and Chad Irschick
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