Remove sccache (#5206)

* Remove sccache

* CI docs

1 files changed, 23 insertions, 5 deletions

diff --git a/docs/ci.md b/docs/ci.md
index bfb101dff..fb4c7e68b 100644
--- a/docs/ci.md
+++ b/docs/ci.md
@@ -1,18 +1,36 @@
 # Our CI
 
-There are github actions for testing building and testing slang.
+There are github actions for building and testing slang.
 
 ## Tests
 
-Most configurations run a restricted set of tests, however on some self hosted runners we run the full test suite, as well as running Falcor's test suite with the new slang build.
+Most configurations run a restricted set of tests, however on some self hosted
+runners we run the full test suite, as well as running Falcor's test suite with
+the new slang build.
 
 ## Building LLVM
 
-We require a static build of LLVM for building slang-llvm, we build and cache this in all workflow runs. Since this changes infrequently, the cache is almost always hit. A cold build takes about an hour on the slowest platform. The cached output is a few hundred MB, so conceivably if we add many more platforms we might be caching more than the 10GB github allowance, which would necessitate being a bit more complicated in building and tracking outputs here.
+We require a static build of LLVM for building slang-llvm, we build and cache
+this in all workflow runs. Since this changes infrequently, the cache is almost
+always hit. A cold build takes about an hour on the slowest platform. The
+cached output is a few hundred MB, so conceivably if we add many more platforms
+we might be caching more than the 10GB github allowance, which would
+necessitate being a bit more complicated in building and tracking outputs here.
 
-For slang-llvm, this is handled the same as any other dependency, except on Windows Debug builds, where we are required by the differences in Debug/Release standard libraries to always make a release build, this is noted in the ci action yaml file.
+For slang-llvm, this is handled the same as any other dependency, except on
+Windows Debug builds, where we are required by the differences in Debug/Release
+standard libraries to always make a release build, this is noted in the ci
+action yaml file.
+
+Note that we don't use sccache while building LLVM, as it changes very
+infrequently. The caching of LLVM is done by caching the final build product
+only.
 
 ## sccache
 
-The CI actions use sccache, keyed on compiler and platform, this runs on all configurations and significantly speeds up small source change builds. This cache can be safely missed without a large impact on build times.
+> Due to reliability issues, we are not currently using sccache, this is
+> historical/aspirational.
 
+The CI actions use sccache, keyed on compiler and platform, this runs on all
+configurations and significantly speeds up small source change builds. This
+cache can be safely missed without a large impact on build times.