Follow-up: We continued debugging the problem off-list. There were actually two problems:
1. The cache size was too small so a second build never even had a chance to get cache hits. 2. There was a generated header file with unstable content (due to Perl 5.18's randomization of hashes <http://search.cpan.org/dist/perl-5.18.0/pod/perldelta.pod#Hash_randomization> ). -- Joel On 11 August 2015 at 21:45, Joel Rosdahl <j...@rosdahl.net> wrote: > Hi Vijay, > > For me, ccache is not working properly on compiling the already compiled >> build again. I can see "ccache miss" count increasing instead of "ccache >> hit" count. > > > To be able to understand why, it would help to get a ccache log that > contains: > > 1. A compilation of a source file X, leading to a cache miss (and storage > of the result in the cache). > 2. A repeated compilation of the same source file X, leading to a cache > miss (where you expected a cache hit of the previous result). > > The log file you attached only contains cache misses for two *different* > source files. > > However, one thing I noticed in your log is that the manifest file already > exists. This likely means that one of the include files has changed content > between the two compilations. To find out which one, get the path of the > manifest from the ccache log file (search for "Looking for object file hash > in .../<hash>-<length>.manifest") and dump the manifest with this script: > > > https://git.samba.org/?p=ccache.git;a=blob_plain;f=dump-manifest;hb=326bcbfda8709db5ad6c21ff6b0e62f0441d27d9 > > (Or, upgrade to ccache 3.2 and run "ccache --dump-manifest > path/to/the.manifest".) > > You can send the dumped manifest to me (or to the list if it's not too > large) and I'll have a look. > > -- Joel > _______________________________________________ ccache mailing list ccache@lists.samba.org https://lists.samba.org/mailman/listinfo/ccache