sccache/docs/Configuration.md

Available Configuration Options

file

[dist]
# where to find the scheduler
scheduler_url = "http://1.2.3.4:10600"
# a set of prepackaged toolchains
toolchains = []
# the maximum size of the toolchain cache in bytes
toolchain_cache_size = 5368709120
cache_dir = "/home/user/.cache/sccache-dist-client"

[dist.auth]
type = "token"
token = "secrettoken"


#[cache.azure]
# does not work as it appears

[cache.disk]
dir = "/tmp/.cache/sccache"
size = 7516192768 # 7 GiBytes

# See the local docs on more explanations about this mode
[cache.disk.preprocessor_cache_mode]
# Whether to use the preprocessor cache mode
use_preprocessor_cache_mode = true
# Whether to use file times to check for changes
file_stat_matches = true
# Whether to also use ctime (file status change) time to check for changes
use_ctime_for_stat = true
# Whether to ignore `__TIME__` when caching
ignore_time_macros = false
# Whether to skip (meaning not cache, only hash) system headers
skip_system_headers = false
# Whether hash the current working directory
hash_working_directory = true

[cache.gcs]
# optional oauth url
oauth_url = "..."
# optional deprecated url
deprecated_url = "..."
rw_mode = "READ_ONLY"
# rw_mode = "READ_WRITE"
cred_path = "/psst/secret/cred"
bucket = "bucket"
key_prefix = "prefix"

[cache.gha]
url = "http://localhost"
token = "secret"
cache_to = "sccache-latest"
cache_from = "sccache-"

[cache.memcached]
url = "..."

[cache.redis]
url = "redis://user:passwd@1.2.3.4:6379/1"

[cache.s3]
bucket = "name"
endpoint = "s3-us-east-1.amazonaws.com"
use_ssl = true
key_prefix = "s3prefix"
server_side_encryption = false

sccache looks for its configuration file at the path indicated by env variable SCCACHE_CONF.

If no such env variable is set, sccache looks at default locations as below:

• Linux: ~/.config/sccache/config
• macOS: ~/Library/Application Support/Mozilla.sccache/config
• Windows: %APPDATA%\Mozilla\sccache\config\config

env

Whatever is set by a file based configuration, it is overruled by the env configuration variables

misc

• SCCACHE_ALLOW_CORE_DUMPS to enable core dumps by the server
• SCCACHE_CONF configuration file path
• SCCACHE_CACHED_CONF
• SCCACHE_IDLE_TIMEOUT how long the local daemon process waits for more client requests before exiting, in seconds. Set to 0 to run sccache permanently
• SCCACHE_STARTUP_NOTIFY specify a path to a socket which will be used for server completion notification
• SCCACHE_MAX_FRAME_LENGTH how much data can be transferred between client and server
• SCCACHE_NO_DAEMON set to 1 to disable putting the server to the background
• SCCACHE_CACHE_MULTIARCH to disable caching of multi architecture builds.

cache configs

disk (local)

• SCCACHE_DIR local on disk artifact cache directory
• SCCACHE_CACHE_SIZE maximum size of the local on disk cache i.e. 2G - default is 10G
• SCCACHE_DIRECT enable/disable preprocessor caching (see the local doc)

s3 compatible

• SCCACHE_BUCKET s3 bucket to be used
• SCCACHE_ENDPOINT s3 endpoint
• SCCACHE_REGION s3 region, required if using AWS S3
• SCCACHE_S3_USE_SSL s3 endpoint requires TLS, set this to true

The endpoint used then becomes ${SCCACHE_BUCKET}.s3-{SCCACHE_REGION}.amazonaws.com. If you are not using the default endpoint and SCCACHE_REGION is undefined, it will default to us-east-1.

cloudflare r2

• SCCACHE_BUCKET is the name of your R2 bucket.
• SCCACHE_ENDPOINT must follow the format of https://<ACCOUNT_ID>.r2.cloudflarestorage.com. Note that the https:// must be included. Your account ID can be found here.
• SCCACHE_REGION should be set to auto.

redis

• SCCACHE_REDIS full redis url, including auth and access token/passwd
• SCCACHE_REDIS_TTL ttl for redis cache, don't set for default behavior.

The full url appears then as redis://user:passwd@1.2.3.4:6379/1.

memcached

• SCCACHE_MEMCACHED memcached url

gcs

• SCCACHE_GCS_BUCKET
• SCCACHE_GCS_CREDENTIALS_URL
• SCCACHE_GCS_KEY_PATH
• SCCACHE_GCS_RW_MODE

azure

• SCCACHE_AZURE_CONNECTION_STRING

gha

• SCCACHE_GHA_CACHE_URL / ACTIONS_CACHE_URL GitHub Actions cache API URL
• SCCACHE_GHA_RUNTIME_TOKEN / ACTIONS_RUNTIME_TOKEN GitHub Actions access token
• SCCACHE_GHA_CACHE_TO cache key to write
• SCCACHE_GHA_CACHE_FROM comma separated list of cache keys to read from