Class GzipUtils

java.lang.Object
ubic.gemma.core.util.GzipUtils
public final class GzipUtils extends Object
gzip at the deflate level Gemma uses for what it generates: data files, their in-band streams and REST responses.

The level is 4, not zlib's default of 6. Measured with zlib on payloads taken from production, 2026-09-18: 

                                                    level 6            level 4
datasets/MSSM_Cohort/singleCellDimension  186 MB    12.0 s  23.1 MB    1.9 s  24.2 MB
datasets/GSE19804/data/processed           49 MB     4.5 s  19.2 MB    1.3 s  20.8 MB
  singleCellDimension?exclude=cellIds      63 MB     1.2 s   2.7 MB    0.3 s   3.2 MB
Expression data and cell ids compress poorly at any level, so level 6 buys a few percent for three to six times the time, and that time is paid by whoever is waiting for the file or the response. Paul, 2026-09-18: level 4. The cell ids are the worst case: high-entropy strings sharing long prefixes (Donor_1-2-AGAGAATGTTAATCGC-1) defeat the long match chains of levels 5 and up. Levels 1 and 2 are another 0.5 s faster on the first payload but 21 to 43% larger than level 4 on smaller, more compressible ones; level 3 is slower than 4.

Not used for the database blob behind CompressedStringListType, nor for files the GEO loader writes.