Why don't operating systems gzip their startup files?
ZachPruckowski: When you're seeking to an idle disk, three things have an impact on speed:  Seek time, file fragmentation, and file size.  Given that your max throughput to any modern HDD is measured in megabytes per second, file size isn't the limiting factor.  You've got to get the drive spinning, get the drive head to the right spot, and read it.  If there's a pile of files, you've got to do that dozens of times if they're not stored near each other on disk.  Compressing the files doesn't really solve this problem.  What one might try, however, is arranging the disk storage such that the files are physically close to each other.  One could even go so far as to mash all the startup stuff into one super-file.To see this in benchmark form, look at the difference in drive speed tests between large reads (sequential) and small reads (random).  You'll go from 60 Mb/s to 6 Mb/s when file size drops from gigabytes to kilobytes, because more of the time is spent seeking.