Re: We have GC problem

We have probem with this one our java biometrics server. Server is
doing too much GCs. The JProbe analyzer says class Bio_lMx315 and
Bio_lMx317 are big problem for us. These class is mostly list of double
like this:

class Bio_lMx315 {
private double chain_315, obp, dbp, lbp, oby, dby, lby;
private double divergence_chain_315, d_obp, d_dbp, d_lbp, d_oby, d_dby,
d_lby;
private String chainName;
private double rtotal_obp, rtotal_dbp, rtotal_lbp, rtotal_oby,
rtotal_dby, rtotal_lby;

private double total_obp, total_dbp, total_lbp, total_oby, total_dby,
total_lby;

...
}

This other classes like Bio_lMx317 looks the same, but for diferent
chain and maybe have little more or little less double.

We getting too many request to compute the chain and the total plus
those regressions and server is doing too much GC and become slow and
we have to kill it. We are not really java programmer! There is three
of us and we don't know all this codes written from a java consultant,
but we have to fix it soon. We thought using object recycling. What do
you think about that? So we don't use new Bio_lMx315 and those other
each time we getting those request, but we have a long cache of them.
We take one out, use them then put it back for use later. I read in
this group someone said you must know the "Life Cycel" of your object.
We know that. We know when use need it and when we do not need them no
longer because computing done. Can you share your comments please? We
don't have lots of time and we must fixing the problems soon.

Server work like this (this is in comment from original programmer):
Utilize a thread pool to divide the biometric modeling work:
BioReceiver directs requests to worker threads (one group for each
chain as persisted in bm_persist_db.ChainDesc). Each worker thread owns
a call back into BioReceiver to notify of completion, results and
problems.

We know to modify this BioReceiver, but we don't want to touch all
those threading codes. We can put the long cache in this BioReceiver
because he doing the BioChain thisRequest = new Bio_lMx315(); and all
those thing.

Please no suggestion about "tweak" -xms params. WE wasting so much time
with this and server will always have problems.