How to prevent very very large ccaches? Nicolas.Williams at
Thu Jun 13 17:14:47 EDT 2002

Er, rather, the fix might be to clear KRB5_TC_OPENCLOSE in krb5_get_credentials().

This should improve SSH/KRSH/FTP performance when multiple instances startup simultaneously. Instead of multiple processes contending for the ccache lock as they read each ccache entry (with all the context switching that that implies) each process would get a lock for the ccache once and otherwise running the ccache sequencing to completion before giving up the lock.

Is there any reason not to clear KRB5_TC_OPENCLOSE in krb5_get_credentials()?

I'll test this and see. Expect results next week. If it works I'll submit a bug report.



> -----Original Message-----
> From: Williams, Nicolas 
> Sent: Thursday, June 13, 2002 5:03 PM
> To: Sam Hartman
> Cc: kerberos at
> Subject: Re: How to prevent very very large ccaches?
> Looking through the source, it seems that clearing the 
> ccache flag while sequencing the ccache, in krb5_cc_retrieve_cred()
> *might* help.
> Nico
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