If cacheDir takes up more than maxCacheSize
megabytes on disk, files will be removed in order of access time by
default. Only files matching extensions are eligible for removal.
Files can also be removed in order of change time with sortBy='ctime'
or modification time with sortBy='mtime'.
The maxFileAge parameter can also be used to remove files that haven't
been modified in a certain number of days. Fractional days are allowed. This
removal happens without regard to the size of the cache and is useful for
removing out-of-date data.
It is important to understand precisely what these timestamps represent:
atime -- File access time: updated whenever a file is opened.
ctime -- File change time: updated whenever a file's metadata
changes e.g. name, permission, ownership.
mtime -- file modification time: updated whenever a file's
contents change.
manageCache(
cacheDir = NULL,
extensions = c("html", "json", "pdf", "png"),
maxCacheSize = 100,
sortBy = "atime",
maxFileAge = NULL
)Location of cache directory.
Vector of file extensions eligible for removal.
Maximum cache size in megabytes.
Timestamp to sort by when sorting files eligible for removal.
One of atime|ctime|mtime.
Maximum age in days of files allowed in the cache.
Invisibly returns the number of files removed.
library(MazamaCoreUtils)
# Create a cache directory and fill it with 1.6 MB of data
CACHE_DIR <- tempdir()
write.csv(matrix(1,400,500), file=file.path(CACHE_DIR,'m1.csv'))
write.csv(matrix(2,400,500), file=file.path(CACHE_DIR,'m2.csv'))
write.csv(matrix(3,400,500), file=file.path(CACHE_DIR,'m3.csv'))
write.csv(matrix(4,400,500), file=file.path(CACHE_DIR,'m4.csv'))
for (file in list.files(CACHE_DIR, full.names=TRUE)) {
print(file.info(file)[,c(1,6)])
}
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/downlit 352
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/downlit 2025-12-31 17:53:52
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d28546d89 226
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d28546d89 2025-12-31 17:53:54
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d36228591 472
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d36228591 2025-12-31 17:53:57
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d53f500c1 436
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d53f500c1 2025-12-31 17:53:55
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d7a04a9f6 336
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d7a04a9f6 2025-12-31 17:53:56
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d95f35a2 222
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d95f35a2 2025-12-31 17:53:53
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m1.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m1.csv 2025-12-31 17:53:58
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m2.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m2.csv 2025-12-31 17:53:58
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m3.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m3.csv 2025-12-31 17:53:58
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m4.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m4.csv 2025-12-31 17:53:58
# Remove files based on access time until we get under 1 MB
manageCache(CACHE_DIR, extensions='csv', maxCacheSize=1, sortBy='atime')
for (file in list.files(CACHE_DIR, full.names=TRUE)) {
print(file.info(file)[,c(1,6)])
}
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/downlit 352
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/downlit 2025-12-31 17:53:52
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d28546d89 226
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d28546d89 2025-12-31 17:53:54
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d36228591 472
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d36228591 2025-12-31 17:53:57
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d53f500c1 436
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d53f500c1 2025-12-31 17:53:55
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d7a04a9f6 336
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d7a04a9f6 2025-12-31 17:53:56
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d95f35a2 222
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d95f35a2 2025-12-31 17:53:53
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m3.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m3.csv 2025-12-31 17:53:58
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m4.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m4.csv 2025-12-31 17:53:58
# Or remove files based on modification time
manageCache(CACHE_DIR, extensions='csv', maxCacheSize=1, sortBy='mtime')
for (file in list.files(CACHE_DIR, full.names=TRUE)) {
print(file.info(file)[,c(1,6)])
}
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/downlit 352
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/downlit 2025-12-31 17:53:52
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d28546d89 226
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d28546d89 2025-12-31 17:53:54
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d36228591 472
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d36228591 2025-12-31 17:53:57
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d53f500c1 436
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d53f500c1 2025-12-31 17:53:55
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d7a04a9f6 336
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d7a04a9f6 2025-12-31 17:53:56
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d95f35a2 222
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/file781d95f35a2 2025-12-31 17:53:53
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m3.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m3.csv 2025-12-31 17:53:58
#> size
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m4.csv 405687
#> atime
#> /var/folders/w_/wx_cnlqj3_v_hq0qrb8tmplr0000gn/T//Rtmp9BJlnN/m4.csv 2025-12-31 17:53:58