Resume from hibernation times are greatly increased after installing Symantec Drive Encryption (SDE). This applies to any Intel hardware running PGP Whole Disk Encryption 10.x version up to and including 10.2.1 as well as Symantec Encryption Desktop 10.3.0 release (current)
This is due to known limitations in our preboot environment and the legacy/MBR BIOS boot mode which is still very commonly used in business environments today due to compatability reasons. Expected behavior will be 3-4 times the normal bootup process on a regular resume from hibernation process. The problem can be worse on some systems with Advanced Format drives due to the vendors implimentation of the 512-byte emulation mode or if the system has more than 4GB of ram and 64-bit Windows.
To solve this issue please upgrade to Symantec Encryption Desktop 10.3.2 or above.
As per the Resolved issues document mentioned in the below link
Resolved an issue with Symantec Drive Encryption to achieve a significantly faster resume time from hibernation following disk encryption. 
Microsoft Windows (32-bit and 64-bit) - 64-bit is most affected by this issue
Symantec Drive Encryption (or PGP Whole Disk Encryption)
Hibernation enabled and in use with Windows
Legacy/MBR BIOS mode