Document x Byte Hit Ratio

Hello there,

How is it possible for Byte-Hit-Ratio to be <0 ?

One of my chaches:
 .....
 Cache information for squid:
        Request Hit Ratios: 5min: 35.0%, 60min: 35.4%
        Byte Hit Ratios: 5min: -4.1%, 60min: -8.4%
 ....

I indeed know that some times, Byte-Hit-Ratio must be less
than zero, because I'm monitoring traffic of these
machines. Sometimes I see losses of more than 500kbps.

In any case, for this to happen, the number of
bytes entering the cache must be grater than the
number of bytes leaving the cache.

Why does this happen? Is it because of aborted request?
I've tried to minimize that with something like this:
 quick_abort_min 1 KB
 quick_abort_max 1 KB
 quick_abort_pct 950

Can this be caused by ICP traffic?
Is it that the request itself is very big? On an aborted
request this could matter (and I have 20% of those).

Thanks,
jp

PS: anyway most of the times the caches are gaining traffic :-)

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